diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 5f75f64fc16..b74143a4512 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -160,6 +160,8 @@ repos:
           ]
         pass_filenames: false # Run on all files
       - id: php-lint
+        exclude:
+          (?x)^(htdocs/includes/symfony/.*)$
       - id: php-stan
         stages: [manual]
         files: \.(php)$
diff --git a/htdocs/commande/class/commande.class.php b/htdocs/commande/class/commande.class.php
index 74f7c62ce1e..e3b381a518a 100644
--- a/htdocs/commande/class/commande.class.php
+++ b/htdocs/commande/class/commande.class.php
@@ -1582,7 +1582,7 @@ class Commande extends CommonOrder
 			$pu_ht = price2num($pu_ht);
 			$pu_ht_devise = price2num($pu_ht_devise);
 			$pu_ttc = price2num($pu_ttc);
-			$pa_ht = (float) price2num($pa_ht);
+			$pa_ht = price2num($pa_ht); // do not convert to float here, it breaks the functioning of $pa_ht_isemptystring
 			if (!preg_match('/\((.*)\)/', (string) $txtva)) {
 				$txtva = price2num($txtva); // $txtva can have format '5,1' or '5.1' or '5.1(XXX)', we must clean only if '5,1'
 			}
@@ -1717,7 +1717,7 @@ class Commande extends CommonOrder
 			$this->line->date_end = $date_end;
 
 			$this->line->fk_fournprice = $fk_fournprice;
-			$this->line->pa_ht = $pa_ht;
+			$this->line->pa_ht = $pa_ht;	// Can be '' when not defined or 0 if defined to 0 or a price value
 
 			// Multicurrency
 			$this->line->fk_multicurrency = $this->fk_multicurrency;
@@ -1727,7 +1727,7 @@ class Commande extends CommonOrder
 			$this->line->multicurrency_total_tva 	= (float) $multicurrency_total_tva;
 			$this->line->multicurrency_total_ttc 	= (float) $multicurrency_total_ttc;
 
-			// TODO Ne plus utiliser
+			// TODO Do not use anymore
 			$this->line->price = $price;
 
 			if (is_array($array_options) && count($array_options) > 0) {
diff --git a/htdocs/commande/class/orderline.class.php b/htdocs/commande/class/orderline.class.php
index a311ef25233..d4ee988d3ea 100644
--- a/htdocs/commande/class/orderline.class.php
+++ b/htdocs/commande/class/orderline.class.php
@@ -345,6 +345,7 @@ class OrderLine extends CommonOrderLine
 		$error = 0;
 
 		$pa_ht_isemptystring = (empty($this->pa_ht) && $this->pa_ht == ''); // If true, we can use a default value. If this->pa_ht = '0', we must use '0'.
+		$this->pa_ht = (float) $this->pa_ht; // convert to float but after checking if value is empty
 
 		dol_syslog(get_class($this)."::insert rang=".$this->rang);
 
@@ -385,14 +386,11 @@ class OrderLine extends CommonOrderLine
 		if (empty($this->fk_parent_line)) {
 			$this->fk_parent_line = 0;
 		}
-		if (empty($this->pa_ht)) {
-			$this->pa_ht = 0;
-		}
 		if (empty($this->ref_ext)) {
 			$this->ref_ext = '';
 		}
 
-		// if buy price not defined, define buyprice as configured in margin admin
+		// if buy price not defined (if = ''), we set the buyprice as configured in margin admin setup
 		if ($this->pa_ht == 0 && $pa_ht_isemptystring) {
 			$result = $this->defineBuyPrice($this->subprice, $this->remise_percent, $this->fk_product);
 			if ($result < 0) {