Hiring a subcontractor requires that you first identify the work you want done, get references from your social network and interview a number of sub-contractors before settling on one. Coming up with a contract that the subcontractor would be willing to sign is also important.
Use trusted sources of references, such as family and friends who have done similar projects. Good sources of references can also be employees of hardware stores and people in the construction industry.
Interview more than one subcontractor, and get bids from each of them. It is acceptable to haggle during the interview stage, though most of the negotiations happen after you settle on one of them and before signing the contract. Specifying the work you want done and the materials you plan to use helps in getting an accurate estimate from the subcontractors.
Do a background check on the subcontractor to determine how often problems arise and how quickly and professionally he is able to resolve disputes or complaints. Remember also to ask the subcontractor for a copy of his license.
Do not rely on a verbal agreement. Putting the deal in writing ensures that the scope and cost of the work is clear to all the parties involved. Due dates and the progress checkpoints are also clarified in the contract.