First of all make sure your contractor is licensed and has insurance. I think his price is way to low. You should figure at least $200.00 per square foot . A complete renovation will include every contractor trade and interior furnishings, cabinets, toilets, fixtures and on. The best first step is to get a complete COMPLETE architectual drawing of the project. Than there will be no suprises or additional costs, include interior elevations of rooms and finishes. There are homes constructed for less per sq.ft. but they are by builders who have standards and all trades now what is expected and comply it is smooth and no change or owner taste is involved. The project runs smoothly as everyone knows to get paid you need to work together and complete your contract as fast as possible. With work for customers there is often changes and workers who do not normally work together and each is competeing for space, recognition and completion regardless of other needs. Pay an architect for a complete set of plans that you understand so than any questions will be directed to the plans, always go to the plans the architect should be available in case of discrepencies.
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