It all depends on the customer for me. If it's a new customer, and their "throw away" is within a year or two, I'll put a little effort into it. But they know it won't be much.
I'll throw on a new plug, filter & lines. If the carb is bad, I'll put on a new Amazon carb. But I'm not going to rebuild one.
As far as the pull cord, it's got to be easy to replace. Not one of those that has to be completely disassembled first.