Ask the store manager @ BM

Marlo, I just went through this. Some thoughts:

1) IMO, Angie's List is worth the money to immediately screen out bad contractors.
2) Check the CCB number with your state licensing board and make sure they have up to date insurance (you should be able to check online)
3) Have them come over and get a quote. With stairs, some will spray and others will brush. Talk to them about your specific concerns (brush strokes, etc.). Ask them how many stair cases they've done recently.
4) Get referrals (preferably on a completed staircase job) and talk to those owners. Talk about the quality as well as the cleanliness of the job (was trash left all over the place overnight, etc.).
5) Ensure that the contractor is easy to contact. Often these guys are out pricing jobs while the crew is there (who may not have great spoken English skills).

Even after all this is done you will want to be there during the job. Be picky through the entire process. Prep is crucial. Do not accept shortcuts. If they know you're checking the work the temptation to cover something up is much less.

Be willing to pay a fair price for a quality job.

That's the number one requirement before you shop.

Hello that si a hard question to answer but I agree with one of the above people get names of people that they painted for on stairs and get permission to use them as a referance also do some homework of your own on the contractors name and find out what his quality reputation is do not put him a the spot by getting and exact sart finish time you want a good job not a rush job and any contractor worth beans will always be honest with you and all professionals will tell you it will be plus or minus 20% of the original quote of time and money cause you never knowe what unforeseen problems could arise you have to do a back ground check on at least 3 to 6 people be has done jobs for one is not good enough he needs a good all around batting record