what is the average prices for sending, stain, 3 coats of finish. I mean the separate price step by step.

When I asked my sand and finish guy that question he said "It's all the same price". People always want him to do the hard part...the sanding. Then they want to do the easy part to save money...only the stain and finish part are the tricky parts where you can really screw up the job and have to sand it over.

I think finish guys get annoyed when people ask that question.

Actually I am trying to build up the price list for the customer. I have experience in doing hardwood floors and finishing them but never work as a contractor so I am not sure about the prices, so that is what I am trying to figure out.

I wouldn't break it down for customers. Just a one number deal. Call around and ask your competition.

No harm in giving him a peice by piece price. It isn't your fault he screws up. And he will and his wife will be ragging him bad. You will be called in to fix

Its unlikely you would be able to separate the components of a sand and finish job. No reputable finisher would accept and thus become responsible for someone else's prep work.
We have two prices: One for sand and finish natural, plus add X dollars for stain. Period.
We base all jobs on their own merit, so those two prices I mention are for basic work.
FYI, in our neighbourhood, a brown stain, + 2 emulsion and 2 streetshoe will cost you $5.00 per foot (if done by us) You can get a shoemaker in to do it for about $2.00 per foot, and some people think they are getting the same job.
We recently completed a condo job, 4000 sq. ft. of Parquet de Versailles that origionally was to be done in a standard browntone stain. The New York designers opted at the last moment that a black "piano" finish would be better. That added 10 bucks a foot to the base price for finishing, and no-one even wimpered as they wrote the cheque.