Hullo again Mike
My advice is do not use a standard contract directly downloaded from Internet. There are several ways of contracting the work and you must first choose the most appropriate to the type of work you want to do. In others, your responsibility is different under the contract.
In others, the contract is signed between two and a constructor for a small work hardly admit, for example as guarantee, you do not pay him all at the end, keeping you a percentage that you pay later.
Sorry I can not help much but would need some information about the works you pose do.