The most important source of information about a residential tenant’s rights and a landlord’s responsibilities is the written lease agreement. Some landlords prefer oral agreements, but it is more common for them to require the tenant's signature on a written lease—and a written lease protects the tenant more than an oral agreement. Be sure to read the lease carefully before you sign it.

A residential landlord’s ability to charge late fees generally depends on the specific language in the written lease agreement; the state’s landlord-tenant laws that may limit the amount of late fees the landlord can charge and the circumstances in which they can be charged; and the state's contract law.

Contract law in most states recognizes an implied duty of good faith and fair dealing between parties to a contract, and a residential landlord who charges late fees because the tenant is an hour late paying the rent may be in breach of the landlord’s implied duty of good faith and fair dealing—unless, for example, the lease agreement specifies an hour (12:00 p.m.) of the day by which rent is due and states that time is of the essence.

In West Virginia, the lease agreement is indeed a crucial document for understanding the rights of residential tenants and the responsibilities of landlords. A written lease provides clarity and legal protection for both parties more so than an oral agreement. Tenants should thoroughly review and understand the lease before signing. Regarding late fees, West Virginia Code §37-6A-2 allows landlords to charge late fees as specified in the lease agreement. However, the fees must be reasonable and not punitive in nature. The state does not set a specific cap on late fees, but they should be in line with the actual damages the landlord incurs due to late payment. Additionally, the implied duty of good faith and fair dealing, which is recognized in contract law, requires that landlords act fairly and not impose late fees in an unreasonable or excessive manner. For instance, charging a late fee for rent that is only an hour late without a clear stipulation in the lease that 'time is of the essence' could potentially be seen as a breach of this duty. It is advisable for tenants to seek clarification on any such terms before agreeing to the lease, and if disputes arise, they may consider consulting with an attorney to understand their rights and obligations under West Virginia law.