The code you provide to me must be understandable by me. I program in mql so it won't be an issue if it looks right. If it's some crazy mashup of confusion, I won't be able to use it, so I will not pay for it.
When you give me the code, I will open it in the mt4 code editor. I will immediately compile it. If I get any errors, those errors will have to be fixed before I pay you. However, if they're simple enough, I'll fix them myself. If I can't fix them, you'll have to fix them. The program currently works fine, so any errors that might exist in the future do not currently exist.