Having a written agreement for a landlord and a tenant is usually a must to show what they have decided upon. This agreement will outline what the responsibilities and rights of the tenant and the landlord are and provides a starting point for any disagreements.
Usually though, it is generally written up with the intention of stopping any disagreements from occurring in the first place, as all who sign should be aware of all that it entails. This kind of written agreement is essential in making sure that relations between the property owner and the tenant will be good.
Usually, the general specifications in the agreement will cover areas such as rent, how it should be paid, when it should be paid, what happens if it is not paid, deposits, and the process of ending the agreement. Also, it may include things such as property maintenance, utilities, how long the lease is, and what methods of mediation will be offered in the case of any potential disagreements.
In some cases, written agreements will stipulate on things like where you may park, if you can have animals, whether cigarettes are allowed, what happens if something breaks, and how many occupants are allowed in the premises. You may also find that things such as lawn mowing and snow removal are covered, depending on necessity.
Also, the agreement will have all the relevant details for both signees, including phone numbers, email addresses, and physical addresses. It is not uncommon for this to be forgotten and then for trouble to occur because of an inability to contact the other party.
The best agreements will have a section that deals with how disagreements can be mediated. Things such as late rent and potential eviction will be outlined and methods of resolution covered in this section.
You can find template agreements on the internet now days. If you download one of these, make sure you fill in all the relevant sections and adapt where necessary.
You will find every state has a different set of rules and obligations. Remember, if in doubt, get legal advice.