When it comes to home improvement, a project guarantee that assures completion in accordance with the contract is very important. The contract spells out what will be done. The warranty assures that the products will perform as expected. But only the project guarantee will make sure this all comes together.
When considering home improvements, having the broadest gaurantee depends. With a company like Home Depot, a homeowner can be pretty confident that Home Depot is going to do whatever it takes to make the project a success. But with an independent or smaller company, you'd want to know very specifically what the project guarantee covers, and what you need to do if you think the home improvement project has not been completed to the contract specifications.