Everyone wants to save money, but when you start by questioning material costs or markups it can indicate that you may be under budgeting for the project, or will question every choice the contractor makes in the hopes of saving $100. Time is money and when you have a customer who may cause interruptions because they want to buy something themselves to avoid "markup" it can cause major delays. Many times a customer ends up getting the wrong material anyway. This again slows down a contractor that may already be too busy.
As a contractor I can tell you that most reputable contractors probably don't need your job, and if you make things too complicated or troublesome, they will move on to other jobs that don't throw up red flags. Much of what you ask for here is reasonable, but bringing a second contract into the equation can set of some alarms that you may be a difficult customer to work with or even a litigiously minded person who is likely to try and bring a lawsuit whether deserved or not. Anything you want covered should be in the original contract.
A punitive approach to what could be unforseen and atypical delays may be a bad idea. I would suggest offering a bonus for the job being completed early rather than a penalty for it being delayed. If material is ordered, we can't make it arrive faster if something delays the shipment. We recently ordered a bathtub requested by a customer. It was promised by our supplier for a Wednesday delivery. Bad weather hit Texas and it just didn't leave the warehouse until the following Monday. It blew up our schedule for the project and it wasn't anyone's fault or mistake. If we have an employee critical to the project get sick or injured, we may not be able to get things done as originally scheduled. Jobs can get off schedule for a lot of reasons outside the contractor's control. Charging them for those things is likely to turn them away.
We’ve had a number of contractors to our house for a number of items from roof tear off & redo, to gutters and corner boards, whole-house carpet replacement and a basement completion. We know the lingo and the big picture but - whether it’s the timing or the unknown - this has been the most frustrating process ever! If you find a nuts & bolts, studs to baseboards and crown-molding to carpet contractor you can trust, consider yourself one of the lucky 10 across the country. The rest of us are stuck in the wild-west and unfortunately left with an article that’s not even worth updating over the past 2+ years.
Installing a new bathtub is one of the more complicated and expensive projects involved in a bathroom remodel. Not only will you have to purchase the tub itself, you also need to install surrounds and have a plumber come by for the installation work. If you're just replacing the tub, and the surround can stay, your price will be lower than average. If you're having a customized surround built, expect to pay around $3,160.
I can't even get anyone to look and give an estimate to complete a bathroom remodel- just the bathtub/shower part has to be done as the last person who was doing it died- the rest is complete and have all the items and materials already and paid for. once they hear that they are no longer intrested- what do they expect? me to let them rip out what was already done and repay and redone everything all over again so they get more money? and throw out brand new imported Travertine and Spanish tile?