Could you tell me if I have to use how far can you go up or how far can come up when talking about price?
I would do the job for $200. How far can you go/come up?
Could you tell me if I have to use how far can you go up or how far can come up when talking about price?
I would do the job for $200. How far can you go/come up?
When haggling colloquially, the phrase used to ask this would be "How high can/could/will/would you go [for X item]?"
I think that my TV is worth more than that. How high would you go for it?
Your sentence is a little different, as it asks how little they would do the work for:
I would do the job for $200. How low would you go?