Yes, you can give the verbal contract to the home improvement service provider if you can get the contract with the proper reference company. It is not a good practice to perform the contract as per the agreement.
It is better we should have proper agreement with the company to get the advantage of the documentation. It is necessary not to sign the verbal agreement with any company because the verbal contract has not performed well. It is necessary to sign the agreement with the home improvement service provider to get the arrangement with the company to get perfect deal.