diff --git a/htdocs/compta/facture.php b/htdocs/compta/facture.php
index 4e7f7fe1c32..8a35fd7583d 100644
--- a/htdocs/compta/facture.php
+++ b/htdocs/compta/facture.php
@@ -1998,7 +1998,7 @@ if ($action == 'create')
 	if (!empty($soc->id)) $absolute_discount = $soc->getAvailableDiscounts();
 	$note_public = $object->getDefaultCreateValueFor('note_public', (is_object($objectsrc)?$objectsrc->note_public:null));
 	$note_private = $object->getDefaultCreateValueFor('note_private', ((! empty($origin) && ! empty($originid) && is_object($objectsrc))?$objectsrc->note_private:null));
-	
+
 	if (! empty($conf->use_javascript_ajax))
 	{
 		require_once DOL_DOCUMENT_ROOT . '/core/lib/ajax.lib.php';
@@ -2197,7 +2197,7 @@ if ($action == 'create')
 	if ((empty($origin)) || ((($origin == 'propal') || ($origin == 'commande')) && (! empty($originid))))
 	{
 		// Deposit
-		if (empty($conf->global->INVOICE_DISABLE_DEPOSIT)) 
+		if (empty($conf->global->INVOICE_DISABLE_DEPOSIT))
    		{
     	    print '<div class="tagtr listofinvoicetype"><div class="tagtd listofinvoicetype">';
     		$tmp='<input type="radio" id="radio_deposit" name="type" value="3"' . (GETPOST('type') == 3 ? ' checked' : '') . '> ';
@@ -2208,7 +2208,7 @@ if ($action == 'create')
     			});
     		});
     		</script>';
-    
+
     		$desc = $form->textwithpicto($tmp.$langs->trans("InvoiceDeposit"), $langs->transnoentities("InvoiceDepositDesc"), 1, 'help', '', 0, 3);
     		print '<table class="nobordernopadding"><tr><td>';
     		print $desc;
@@ -2222,7 +2222,7 @@ if ($action == 'create')
     			print '<td class="nowrap" style="padding-left: 5px">' . $langs->trans('Value') . ':<input type="text" id="valuedeposit" name="valuedeposit" size="3" value="' . GETPOST('valuedeposit', 'int') . '"/>';
     		}
     		print '</td></tr></table>';
-    
+
     		print '</div></div>';
    		}
 	}
@@ -2254,7 +2254,7 @@ if ($action == 'create')
 		}
 
 		// Replacement
-		if (empty($conf->global->INVOICE_DISABLE_REPLACEMENT)) 
+		if (empty($conf->global->INVOICE_DISABLE_REPLACEMENT))
 		{
     		print '<!-- replacement line -->';
     		print '<div class="tagtr listofinvoicetype"><div class="tagtd listofinvoicetype">';
@@ -2301,7 +2301,7 @@ if ($action == 'create')
 		if ($socid > 0)
 		{
     		// Credit note
-		    if (empty($conf->global->INVOICE_DISABLE_CREDIT_NOTE)) 
+		    if (empty($conf->global->INVOICE_DISABLE_CREDIT_NOTE))
     		{
     			print '<div class="tagtr listofinvoicetype"><div class="tagtd listofinvoicetype">';
     			$tmp='<input type="radio" id="radio_creditnote" name="type" value="2"' . (GETPOST('type') == 2 ? ' checked' : '');
@@ -2337,12 +2337,12 @@ if ($action == 'create')
     			$text .= '</select>';
     			$desc = $form->textwithpicto($text, $langs->transnoentities("InvoiceAvoirDesc"), 1, 'help', '', 0, 3);
     			print $desc;
-    
+
     			print '<div id="credit_note_options" class="clearboth">';
     	        print '&nbsp;&nbsp;&nbsp; <input data-role="none" type="checkbox" name="invoiceAvoirWithLines" id="invoiceAvoirWithLines" value="1" onclick="if($(this).is(\':checked\') ) { $(\'#radio_creditnote\').prop(\'checked\', true); $(\'#invoiceAvoirWithPaymentRestAmount\').removeAttr(\'checked\');   }" '.(GETPOST('invoiceAvoirWithLines','int')>0 ? 'checked':'').' /> <label for="invoiceAvoirWithLines">'.$langs->trans('invoiceAvoirWithLines')."</label>";
     	        print '<br>&nbsp;&nbsp;&nbsp; <input data-role="none" type="checkbox" name="invoiceAvoirWithPaymentRestAmount" id="invoiceAvoirWithPaymentRestAmount" value="1" onclick="if($(this).is(\':checked\') ) { $(\'#radio_creditnote\').prop(\'checked\', true);  $(\'#invoiceAvoirWithLines\').removeAttr(\'checked\');   }" '.(GETPOST('invoiceAvoirWithPaymentRestAmount','int')>0 ? 'checked':'').' /> <label for="invoiceAvoirWithPaymentRestAmount">'.$langs->trans('invoiceAvoirWithPaymentRestAmount')."</label>";
     			print '</div>';
-    
+
     			print '</div></div>';
     		}
 		}
diff --git a/htdocs/install/mysql/migration/3.8.0-3.9.0.sql b/htdocs/install/mysql/migration/3.8.0-3.9.0.sql
index 86d2549a8bc..88ba07cc24b 100644
--- a/htdocs/install/mysql/migration/3.8.0-3.9.0.sql
+++ b/htdocs/install/mysql/migration/3.8.0-3.9.0.sql
@@ -611,3 +611,7 @@ INSERT INTO llx_c_tva(rowid,fk_pays,taux,recuperableonly,note,active) VALUES (14
 -- VMYSQL4.1 ALTER TABLE llx_c_type_resource CHANGE COLUMN rowid rowid integer NOT NULL AUTO_INCREMENT;
 
 ALTER TABLE llx_import_model MODIFY COLUMN type varchar(50);
+
+-- Negative buying prices
+
+UPDATE llx_facturedet SET buy_price_ht = ABS(buy_price_ht)