I think you should get estimates from licensed and bonded contractors. The answer to your questions depends on too many variables. When you talk to contractors, make sure that you are specific as to what you want done and have them give you bids on the same work. Make sure they itemize labor and material so that you have a way to compare. Ask the contractors for references. Ask friends and family for referrals. You can also contact a local real estate agent to get a referral. Agents usually have qualified contractors whom they trust. Good luck with the project.