From questions asked on here two points of warning :
1. Remember as a business you do not have the same consumer protection as a private individual. To some extent it is presumed you can look after yourself unless it is grossly unfair.
2. Have some short clear terms and conditions and make sure your customers read them. Prevention is better than arguments afterwards, I have a customer who has them on a laminated sheet and makes her clients sit down and read them before signing they understand. Tedious but worth it.