Most reputable home remodeling contractors will have what we term a “Subsurface Clause” in our contracts. It's how this clause is used that differentiates the good guys from the bad guy horror stories you hear about.
Bad Guy Tactic
Let's just call this tactic a form of optimism that only works in the bad guy's favor. It is fairly easy to identify because the bad guy's price will be structured like a bait and switch. He knows when he tears into your walls that certain things are to be expected, but his price is based on unrealistic perfection.
Then when he discovers problems, his low price gets much bigger and he has you over the proverbial barrel. Your final cost ends up being higher than the higher bids you rejected—bids that were actually realistic because they accounted for the problems.
Good Guy Method
An experienced contractor who knows he will find certain things behind the walls and in soffits and adds a certain amount to the quote based on his experience or what might be expected. His price is usually a bit higher than the bad guy, or so it appears, but it is a price based on reality rather than a planned increase.
Although many problems are anticipated in advance and built into the price you are quoted, there are certain things that cannot be discovered until opening up walls in a remodeling project. It's unexpected problems, such as termites for example, that honest contractors must have the Subsurface Clause to cover.
Conclusion
Because our natural desire to save money is so strong, disreputable contractors know exactly how to play into that. The fact that they've gotten so good at it is why you hear all those cases of running seriously over budget and other remodeling woes resulting from bad guy tactics.
Fortunately, the information to recognize their tactics and avoid being taken in is widely available. The very fact that you took time to read this post could save you some serious grief.
My advice is to pay careful attention to the detail put into the quote.
