First of all, this is only my opinion and many others might NOT share this:
I would definately NOT go with home center installer. The reasons, they may be just good handy men/women and might not be the best. Our Local home center changes installers all the time, turnover is horindious. So, it could be the pay and you pay what you get.
I would go the installers from a floor speciality store that has full time installers that might know more or be more professional.
I would also consider checking in the Yellow Pages under flooring installation and get three or four bids and meet the installers in you home. There are many good independant flooring installers out there. Get references from each and DO call them.
Now, a builder should be building homes and making the big bucks. Why would he/she do flooring for only $2.25 sqft? He/she could be making 20 times that in his/her regular profession. Being a builder is not a safe title and one that you should not challenge. I can call myself a builder right now.
In summation, I would seek out a good independant contractor specializing in flooring. Ask for references, ask for pictures, as for suggestions. Get a firm bid and one that is not vague. Get a square foot labor price and have him/her measure it out and give you the total labor job. Get it all down in paper, no later labor costs, no overuns, and one that has wording something like this:
You have all the material on site. He will give you a material list and that should include staples like, new molding, fasteners, caulk, and others. Get a list of the material besides the flooring and vapor barrier and stuff that will be needed.
Then get the labor pay schedule. I work like this, you or I have the material on site and if I got it, I want a check for all material I bought paid to me the first day. Then I get one half one half the way through the job and the balance upon completion. Some do one third, one third and the balance. Whatever you do, do not pay too much up front if any.
Also, when the contractors come out, do not assume that he/she is the one doing the work. ask if he/she is the actual installer or who will be. People feel better when the person doing the bidding will be doing the installation or at least be there to supervise periodically.
Its tough, but you will find someone that you feel good about and comfortable with.