Finalize the product cost calculation constructor on Bitrix

There is a constructor on Bitrix, it has about 3000 lines of code. It is necessary to make edits, there are many of them, since the calculation conditions change. You also need to connect a layout that would draw the product according to the specified parameters. I am looking for a specialist not lower than middle. Beginners do not write. Priority of the Russian Federation and payment by invoice. You can be self-employed. I ask the company not to respond.