multi currency in laravel on ads

I have such a situation on my laraclassified there is no multi currency when adding an ad, only one currency is worth. in the admin panel when specifying the country there is a choice of currency. but there is only one currency you choose. what should the user do when adding an ad could a different currency? for example, euros or dollars? I wrote to the developers, but they respond in a very long time.

// Special parameters
            $specParams = [];
            if ($key == 'minPrice') { // Min. Price
                // $this->arrSql->where[] = $this->filterParametersFields[$key] . ' >= ' . $value;
                $this->arrSql->having[] = $this->filterParametersFields[$key] . ' >= ' . $value;
                $specParams[] = $key;
            }
            if ($key == 'maxPrice') { // Max. Price
                // $this->arrSql->where[] = $this->filterParametersFields[$key] .  ' <= ' . $value;
                $this->arrSql->having[] = $this->filterParametersFields[$key] . ' <= ' . $value;
                $specParams[] = $key;

via Chebli Mohamed