diff --git a/fusion_rental/models/sale_order.py b/fusion_rental/models/sale_order.py
index 4d3b1a4..80959da 100644
--- a/fusion_rental/models/sale_order.py
+++ b/fusion_rental/models/sale_order.py
@@ -836,10 +836,18 @@ class SaleOrder(models.Model):
     # Auto-set sale type for rental orders
     # =================================================================
 
+    @api.onchange('is_rental_order')
+    def _onchange_is_rental_order_sale_type(self):
+        if self.is_rental_order and not self.x_fc_sale_type:
+            self.x_fc_sale_type = 'rental'
+            self.x_fc_authorizer_required = 'no'
+
     @api.model_create_multi
     def create(self, vals_list):
+        in_rental = self.env.context.get('in_rental_app')
         for vals in vals_list:
-            if vals.get('is_rental_order') and not vals.get('x_fc_sale_type'):
+            is_rental = vals.get('is_rental_order', in_rental)
+            if is_rental and not vals.get('x_fc_sale_type'):
                 vals['x_fc_sale_type'] = 'rental'
                 vals.setdefault('x_fc_authorizer_required', 'no')
         return super().create(vals_list)