diff --git a/addons/product/pricelist.py b/addons/product/pricelist.py
index c333000621a..f189b854fe5 100644
--- a/addons/product/pricelist.py
+++ b/addons/product/pricelist.py
@@ -394,6 +394,12 @@ class product_pricelist_item(osv.osv):
                     return False
         return True
 
+    def _check_margin(self, cr, uid, ids, context=None):
+        for item in self.browse(cr, uid, ids, context=context):
+            if item.price_max_margin and item.price_min_margin and (item.price_min_margin > item.price_max_margin):
+                return False
+        return True
+
     _columns = {
         'name': fields.char('Rule Name', size=64, help="Explicit rule name for this pricelist line."),
         'price_version_id': fields.many2one('product.pricelist.version', 'Price List Version', required=True, select=True, ondelete='cascade'),
@@ -401,13 +407,13 @@ class product_pricelist_item(osv.osv):
         'product_id': fields.many2one('product.product', 'Product', ondelete='cascade', help="Set a product if this rule only apply to one product. Keep empty for all products"),
         'categ_id': fields.many2one('product.category', 'Product Category', ondelete='cascade', help="Set a category of product if this rule only apply to products of a category and his children. Keep empty for all products"),
 
-        'min_quantity': fields.integer('Min. Quantity', required=True, help="The rule only applies if the partner buys/sells more than this quantity."),
+        'min_quantity': fields.integer('Min. Quantity', required=True, help="The rule only applies if the partner buys/sells equal to or more than this quantity."),
         'sequence': fields.integer('Sequence', required=True, help="Gives the order in which the pricelist items will be checked. The evaluation gives highest priority to lowest sequence and stops as soon as a matching item is found."),
         'base': fields.selection(_price_field_get, 'Based on', required=True, size=-1, help="The mode for computing the price for this rule."),
         'base_pricelist_id': fields.many2one('product.pricelist', 'If Other Pricelist'),
 
         'price_surcharge': fields.float('Price Surcharge',
-            digits_compute= dp.get_precision('Product Price')),
+            digits_compute= dp.get_precision('Product Price'), help='Specify the fixed amount to add or substract(if negative) to the amount calculated with the discount.'),
         'price_discount': fields.float('Price Discount', digits=(16,4)),
         'price_round': fields.float('Price Rounding',
             digits_compute= dp.get_precision('Product Price'),
@@ -416,15 +422,16 @@ class product_pricelist_item(osv.osv):
               "To have prices that end in 9.99, set rounding 10, surcharge -0.01" \
             ),
         'price_min_margin': fields.float('Min. Price Margin',
-            digits_compute= dp.get_precision('Product Price')),
+            digits_compute= dp.get_precision('Product Price'), help='Specify the minimum amount of margin over the base price.'),
         'price_max_margin': fields.float('Max. Price Margin',
-            digits_compute= dp.get_precision('Product Price')),
+            digits_compute= dp.get_precision('Product Price'), help='Specify the maximum amount of margin over the base price.'),
         'company_id': fields.related('price_version_id','company_id',type='many2one',
             readonly=True, relation='res.company', string='Company', store=True)
     }
 
     _constraints = [
-        (_check_recursion, 'Error ! You cannot assign the Main Pricelist as Other Pricelist in PriceList Item!', ['base_pricelist_id'])
+        (_check_recursion, 'Error! You cannot assign the Main Pricelist as Other Pricelist in PriceList Item!', ['base_pricelist_id']),
+        (_check_margin, 'Error! The minimum margin should be lower than the maximum margin.', ['price_min_margin', 'price_max_margin'])
     ]
 
     def product_id_change(self, cr, uid, ids, product_id, context=None):
diff --git a/addons/product/product_pricelist_demo.yml b/addons/product/product_pricelist_demo.yml
index 39f6cfc16b2..efb812ad5e2 100644
--- a/addons/product/product_pricelist_demo.yml
+++ b/addons/product/product_pricelist_demo.yml
@@ -47,7 +47,7 @@
             - name: 20% Discount given by my supplier
               sequence: 1
               price_min_margin: 2
-              price_max_margin: -5
+              price_max_margin: 5
               product_id: product_product_6
               base: -2
 -
diff --git a/addons/product/test/product_pricelist.yml b/addons/product/test/product_pricelist.yml
index 85230261312..66e256d4cd1 100644
--- a/addons/product/test/product_pricelist.yml
+++ b/addons/product/test/product_pricelist.yml
@@ -49,14 +49,14 @@
   !python {model: product.product}: |
     context.update({'quantity':1, 'date': False, 'partner': ref('base.res_partner_4'), 'pricelist': ref("supplier_pricelist")})
     product = self.browse(cr, uid, ref("product_product_6"), context=context)
-    assert product.price == 785, "cost price is not correspond."
+    assert product.price == 792, "cost price is not correspond."
 -
   I check cost price of LCD Monitor if more than 3 Unit.
 -
   !python {model: product.product}: |
     context.update({'quantity':3})
     product = self.browse(cr, uid, ref("product_product_6"), context=context)
-    assert product.price == 780, "cost price is not correspond."
+    assert product.price == 787, "cost price is not correspond."
 
 -
  I print the sale prices report.