It is important that all contracts include consideration in order for any agreement to be legally binding.
The example of a contract of this type is:
Renting a place to use for your sales business. You rent the place for a certain period of time (Let's say one year) and for a settled amount of money. In form of a lease, is stated and stipulated what that amount of money includes (let's say just the place) and what it doesn't include (energy and water bill) as well as the rules for using and living in the place.
This contract applies for both parts once consideration is provided by accepting the terms of conditions and the value agreed.
