Most of our competition use false sales techniques! They might claim their warranty is the best offered. It sounds way to good to be true, then it usually is. They actually lie about it, to gain your trust and your business. Check Yelp reviews and BBB, before hiring. This will help you understand what kind of business practices, they do.
If the price you received from one company, is way cheaper than the other couple bids you have received, there's usually something wrong and should raise a red flag. If a company is undercutting their competition, then they are undercutting their quality too and that is the kind of job you will get!
Use the #1 rule to start out with - 1st impressions is the best way to start. Is the salesman to pushy? Do they dress the part (a paint company that comes to an estimate in a business suite, doesn't match the industry norm. That is like going to court with painter clothes on)? Does their presentation match what they are saying and if yes, then do your homework after they leave, to back up those claims and to save yourself some headaches.
Never give money down, in a service type of business. If a company can not afford to front the job, then they should not be in business in the 1st place.
No matter what, research the company that you decide to hire, before you sign a contract. If you google a company, yelp and check the BBB, you normally can see what their business practices are. You will save yourself a major hassle from the get go.