It really depends how the contract is written. If the contract states that they they will give you a finished product for a certain amount, then it definitely is on the store. If it states exactly what individual steps they are going to provide and it makes no mention of these extra steps that need taken, then is is a matter of opinion as to whether you should be obligated to pay the extra money. I find it petty that installers try to charge extra placing you in the middle, unless it is an arrangement that you pay the installers direct..which I never agree with. If it you and the store that the deal is between, don't tell me that I have to deal with installers. It really depends how the contract is written, if it is indeed a proposal. My company does many deals as line item quotes and some as proposals. When it is a proposal, we tell them what the end result will be and it is our job to get it to that point for a certain amount of money, unless exceptions are written in the proposal. A line item quote is a little different in my mind as it states what steps will be taken and a price breakdown of each step...On that type it with me a matter of opinion (a judges perhaps) whether you would be obligated for an additional step that was not charged for that is needed and was not realized or couldn't be realized until after the job was commenced. Hopefully I didnt confuse you all the more.

Contractors don't have Xray vision. They can't "know" what conditions will be behind walls or under flooring until the demolition is actually done. At that point, if extra materials are labor are needed to accomplish the job, then a change order to the original contract is needed. There are usually standard clauses in contracts covering this eventuality. If you do not want to pay for the additional material and labor at this point, then you would be obligated to pay for the demolition and then get bids for the job as it appears now from other companies who might be more or might be less. It would be cost additional time to go through this process, so it's in both your best interests to come to some agreement about the extra work and materials needed for your job.

I really wish you would explain what you mean by the contract...as this will help me give you better direction. Is the store paying the sub labor or did they just sell you the tile? x ray vision or no x ray vision..if they gave you a completed price, then incidentals should have been loaded in if there were any uncertainties. Dont low ball a price then up it when your in the middle of it.

The store sold me the tile AND the labor--complete package. They told me the installers were very good, I did not meet them, etc until they came to my home. I had no contact with the installers until they came to my home.

Nope you don't owe them a nickle...extra...It is strictly between the store and the installer...Your payment is only made to the store via the contract I assume...if that is the case they need to complete the job as specified at the original amount. The only difference would be is if they indicated in the contract that extra charge could apply If this or if that....If this verbiage is not in there...Then i don't care if they have to build you another house to complete it..

Now with that said..if you feel there truly is something that needs done that was no way evident or just impossible to tell...it is on you to decide what you want to do...but if the store just wasn't as thorough as it should have been then any other stores bid on your project didn't get an equal chance because they may have figured on doing what ever it took to do the job...it is the way My store would handle that...many times we eat something big time because we missed it in our bid. I cannot go back to the customer..x ray vision or not..it just doesn't work that way....so there you have it. Thanks for listening.

ditto.

right now the store is dancing and skating, so that ultimately there will have been too much time elapsed, and things will get renegotiated (ie. you pay more).

you'll just have to tell them the deal is off unless they stop whining immediately and start working it out fast and professionally.

What was the old subfloor? Tile backer board or concrete? If it was old tile backer board then they should replace it anyway and just put some floor leveler in the low spots which should only take a couple of hours.

Personally, I think they are giving you the run around. If you are bidding a job you can't just go back and say it was "harder than expected". That's part of the bidding process. You either build aggravations into the price and get lucky if it goes easily or you build eventualities into the contract.

Don't pay them anything and tell the contractor to talk to the store. You have a contract with the store, not them. You might want to check your floor too to see how unlevel it is.

Basically, problems taking off the old tile is not your problem. The uneven floor might be your problem and you could certainly hire someone else to level your floors and then stick to the original contract with the original installers.