Having an attorney review the home improvement project contract is a good idea, especially If the home improvement project is sizeable. The basis of most disputes is a lack of communication. An attorney can make sure the project contract is clear and both parties expectations are spelled out. In any event, it is extremely important that you have a written agreement between yourself and the contractor for any size job. Spelling out the scope of the project with a project contract is the best way to assure the finished project is what you expect.
While verbal contracts are valid, they are very difficult to enforce. Disputes over verbal agreements often deteriorate into a he said - she said match where neither party can prove what was agreed to. Therefore, a written home improvement projects cntract, along with written change orders and punch lists is the best way to make sure your home improvement project comes out as expected.