diff --git a/rma/models/rma_order_line.py b/rma/models/rma_order_line.py
index 0a4dfab4..1866a2e3 100644
--- a/rma/models/rma_order_line.py
+++ b/rma/models/rma_order_line.py
@@ -209,9 +209,11 @@ class RmaOrderLine(models.Model):
     )
     assigned_to = fields.Many2one(
         comodel_name='res.users', track_visibility='onchange',
+        default=lambda self: self.env.uid,
     )
     requested_by = fields.Many2one(
         comodel_name='res.users', track_visibility='onchange',
+        default=lambda self: self.env.uid,
     )
     partner_id = fields.Many2one(
         comodel_name='res.partner', required=True, store=True,
@@ -230,7 +232,7 @@ class RmaOrderLine(models.Model):
     product_tracking = fields.Selection(related="product_id.tracking")
     lot_id = fields.Many2one(
         comodel_name="stock.production.lot", string="Lot/Serial Number",
-        readonly=True, states={"new": [("readonly", False)]},
+        readonly=True, states={"draft": [("readonly", False)]},
     )
     product_qty = fields.Float(
         string='Ordered Qty', copy=False,
@@ -481,7 +483,6 @@ class RmaOrderLine(models.Model):
         self.write({'state': 'to_approve'})
         for rec in self:
             if rec.product_id.rma_approval_policy == 'one_step':
-                rec.write({'assigned_to': self.env.uid})
                 rec.action_rma_approve()
         return True
 
@@ -531,8 +532,7 @@ class RmaOrderLine(models.Model):
                 self.product_id.categ_id.rma_supplier_operation_id
         if self.lot_id.product_id != self.product_id:
             self.lot_id = False
-        return {'domain': {
-            'lot_id': [('product_id', '=', self.product_id.id)]}}
+        return result
 
     @api.onchange('operation_id')
     def _onchange_operation_id(self):
diff --git a/rma/views/rma_order_line_view.xml b/rma/views/rma_order_line_view.xml
index e1bb0630..2bc14d06 100644
--- a/rma/views/rma_order_line_view.xml
+++ b/rma/views/rma_order_line_view.xml
@@ -110,6 +110,22 @@
                                    domain="[('supplier','=',True)]"
                                    string="Supplier"/>
                         </group>
+                        <group>
+                            <group name="product" string="Product">
+                                <field name="product_id"/>
+                                <newline/>
+                                <field name="product_tracking" invisible="1"/>
+                                <field name="lot_id"
+                                       groups="stock.group_production_lot"
+                                       attrs="{'required': [('product_tracking', 'in', ('serial', 'lot'))]}"
+                                       domain="[('product_id', '=', product_id)]"/>
+                            </group>
+                            <group name="product_qty" string="Quantity">
+                                <field name="product_qty"/>
+                                <field name="price_unit"/>
+                                <field name="uom_id" groups="product.group_uom"/>
+                            </group>
+                        </group>
                         <group name="main_info" string="Origin">
                             <field name="reference_move_id"
                                    options="{'no_create': True}"
@@ -118,20 +134,6 @@
                                             ('state', '=', 'done')]"/>
                         </group>
                         <group>
-                            <group name="product" string="Product">
-                                <field name="product_id"/>
-                                <newline/>
-                                <field name="product_tracking" invisible="1"/>
-                                <field name="lot_id"
-                                       groups="stock.group_production_lot"
-                                       attrs="{'required': [('product_tracking', 'in', ('serial', 'lot'))]}"/>
-                            </group>
-                            <group name="product_qty" string="Quantity">
-                                <field name="product_qty"/>
-                                <field name="price_unit"/>
-                                <field name="uom_id" groups="product.group_uom"/>
-                            </group>
-                            <newline/>
                             <group name="operation" string="Operation">
                                 <field name="operation_id"
                                        domain="[('type','=','supplier')]"/>
@@ -140,7 +142,7 @@
                             </group>
                             <group name="contact" string="Contact">
                                 <field name="requested_by" readonly="1"/>
-                                <field name="assigned_to" readonly="1"/>
+                                <field name="assigned_to"/>
                             </group>
                         </group>
                         <notebook>
@@ -279,6 +281,22 @@
                                 <field name="under_warranty"/>
                             </group>
                         </group>
+                        <group>
+                            <group name="product" string="Product">
+                                <field name="product_id"/>
+                                <newline/>
+                                <field name="product_tracking" invisible="1"/>
+                                <field name="lot_id"
+                                       groups="stock.group_production_lot"
+                                       attrs="{'required': [('product_tracking', 'in', ('serial', 'lot'))]}"
+                                       domain="[('product_id', '=', product_id)]"/>
+                            </group>
+                            <group name="product_qty" string="Quantity">
+                                <field name="product_qty"/>
+                                <field name="uom_id" groups="product.group_uom"/>
+                                <field name="price_unit"/>
+                            </group>
+                        </group>
                         <group name="main_info" string="Origin">
                             <field name="reference_move_id"
                                    options="{'no_create': True}"
@@ -287,20 +305,6 @@
                                             ('state', '=', 'done')]"/>
                         </group>
                         <group>
-                            <group name="product" string="Product">
-                                <field name="product_id"/>
-                                <newline/>
-                                <field name="product_tracking" invisible="1"/>
-                                <field name="lot_id"
-                                       groups="stock.group_production_lot"
-                                       attrs="{'required': [('product_tracking', 'in', ('serial', 'lot'))]}"/>
-                            </group>
-                            <group name="product_qty" string="Quantity">
-                                <field name="product_qty"/>
-                                <field name="uom_id" groups="product.group_uom"/>
-                                <field name="price_unit"/>
-                            </group>
-                            <newline/>
                             <group name="operation" string="Operation">
                                 <field name="operation_id" domain="[('type','=','customer')]"/>
                                 <field name="receipt_policy"/>
@@ -308,7 +312,7 @@
                             </group>
                             <group name="contact" string="Contact">
                                 <field name="requested_by" readonly="1"/>
-                                <field name="assigned_to" readonly="1"/>
+                                <field name="assigned_to"/>
                             </group>
                         </group>
                         <notebook>
diff --git a/rma_account/models/rma_order_line.py b/rma_account/models/rma_order_line.py
index 375f9583..860bf8bb 100644
--- a/rma_account/models/rma_order_line.py
+++ b/rma_account/models/rma_order_line.py
@@ -79,19 +79,19 @@ class RmaOrderLine(models.Model):
         digits=dp.get_precision('Product Unit of Measure'),
         readonly=True, compute=_compute_qty_refunded, store=True)
 
-    @api.onchange('product_id')
+    @api.onchange('product_id', 'partner_id')
     def _onchange_product_id(self):
+        """Domain for invoice_line_id is computed here to make it dynamic."""
         res = super(RmaOrderLine, self)._onchange_product_id()
-        if res.get('domain') and self.product_id:
-            res['domain']['invoice_line_id'] = [
-                ('product_id', '=', self.product_id.id)]
-        elif res.get('domain') and self.product_id:
-            res['domain']['invoice_line_id'] = [()]
-        elif not res.get('domain') and self.product_id:
-            res['domain'] = {
-                'invoice_line_id': [('product_id', '=', self.product_id.id)]}
-        else:
-            res['domain'] = {'invoice_line_id': []}
+        if not res.get('domain'):
+            res['domain'] = {}
+        domain = [
+            '|',
+            ('invoice_id.partner_id', '=', self.partner_id.id),
+            ('invoice_id.partner_id', 'child_of', self.partner_id.id)]
+        if self.product_id:
+            domain.append(('product_id', '=', self.product_id.id))
+        res['domain']['invoice_line_id'] = domain
         return res
 
     @api.multi
diff --git a/rma_account/views/rma_order_line_view.xml b/rma_account/views/rma_order_line_view.xml
index 166b9c16..799a7a70 100644
--- a/rma_account/views/rma_order_line_view.xml
+++ b/rma_account/views/rma_order_line_view.xml
@@ -17,10 +17,7 @@
                 </button>
                 <group name="main_info" position="inside">
                     <field name="invoice_line_id"
-                           options="{'no_create': True}"
-                           domain="['|',
-                                    ('invoice_id.partner_id', '=', partner_id),
-                                    ('invoice_id.partner_id', 'child_of', partner_id)]"/>
+                           options="{'no_create': True}"/>
                 </group>
                 <field name="operation_id" position="after">
                     <field name="refund_policy"/>
@@ -64,10 +61,7 @@
                 </button>
                 <group name="main_info" position="inside">
                     <field name="invoice_line_id"
-                           options="{'no_create': True}"
-                           domain="['|',
-                                    ('invoice_id.partner_id', '=', partner_id),
-                                    ('invoice_id.partner_id', 'child_of', partner_id)]"/>
+                           options="{'no_create': True}"/>
                 </group>
                 <field name="operation_id" position="after">
                     <field name="refund_policy"/>
diff --git a/rma_sale/models/rma_order_line.py b/rma_sale/models/rma_order_line.py
index 85ca419a..43332104 100644
--- a/rma_sale/models/rma_order_line.py
+++ b/rma_sale/models/rma_order_line.py
@@ -64,19 +64,19 @@ class RmaOrderLine(models.Model):
     sales_count = fields.Integer(
         compute=_compute_sales_count, string='# of Sales')
 
-    @api.onchange('product_id')
+    @api.onchange('product_id', 'partner_id')
     def _onchange_product_id(self):
+        """Domain for sale_line_id is computed here to make it dynamic."""
         res = super(RmaOrderLine, self)._onchange_product_id()
-        if res.get('domain') and self.product_id:
-            res['domain']['sale_line_id'] = [
-                ('product_id', '=', self.product_id.id)]
-        elif res.get('domain') and self.product_id:
-            res['domain']['sale_line_id'] = [()]
-        elif not res.get('domain') and self.product_id:
-            res['domain'] = {
-                'sale_line_id': [('product_id', '=', self.product_id.id)]}
-        else:
-            res['domain'] = {'sale_line_id': []}
+        if not res.get('domain'):
+            res['domain'] = {}
+        domain = [
+            '|',
+            ('order_id.partner_id', '=', self.partner_id.id),
+            ('order_id.partner_id', 'child_of', self.partner_id.id)]
+        if self.product_id:
+            domain.append(('product_id', '=', self.product_id.id))
+        res['domain']['sale_line_id'] = domain
         return res
 
     @api.onchange('operation_id')
diff --git a/rma_sale/views/rma_order_line_view.xml b/rma_sale/views/rma_order_line_view.xml
index fe3407ff..c82596de 100644
--- a/rma_sale/views/rma_order_line_view.xml
+++ b/rma_sale/views/rma_order_line_view.xml
@@ -18,10 +18,7 @@
                 </div>
                 <group name="main_info" position="inside">
                     <field name="sale_line_id"
-                           options="{'no_create': True}"
-                           domain="['|',
-                                    ('order_id.partner_id', '=', partner_id),
-                                    ('order_id.partner_id', 'child_of', partner_id)]"/>
+                           options="{'no_create': True}"/>
                 </group>
                 <group name="quantities" position="inside">
                     <group>