Legal Ability Must Exist
You and the individual or company entering into a formal contract agreement must both be of legal age and have legal rights to enter into the paving agreement, For example, a minor will not be held legally responsible for paying you for work completed if they hire you and refuse to pay. Likewise, paving a property not owned by the individual contracting with you can create complications if you have to seek payment through the court system.
Consideration Must Exist
A legal "consideration" must be in place. Another word for this is quid pro quo. You have to be getting something in return for what you are being asked to do by another in the contract. As the homeowner, you must agree to pay the paving company for the paving job that they promise to do. A legal requirement for any contract is that both parties receive a "consideration" for what they are promising to do.
A contract must have the terms of the agreement outlined completely. Each party to the contract should understand what is required of them in the formal written agreement. Expressing the expected date the paving project will begin and end, along with the area of ground to be paved in total measurement terms or distance, as well as the date and method of payment for paving services must all be included. You also have to include information about possible repercussions if the terms are not met. This ensures each party in the contract knows what is expected of them and what happens if they do not comply.
Your contract should include a clause that addresses who will be responsible for excavation or utility markings -- especially if your paving project is only part of an overall landscaping project with a client. Your contract should also include who will be responsible for obtaining the paving permit, what type of warranty will be given for the project -- and the limitation of that warranty -- as well as how much it will cost to change the paving work order once work has begun. Finally, a paving contract should include a non-refundable deposit clause. If the project is canceled this deposit can help reduce your overall losses. You don't have to have a professional draw up your paving contract, necessarily, but it is a good idea to do so if you can afford it. Otherwise, you can follow a general format -- changing the wording to reflect your paving project particulars -- by using a free sample.