There are three sources of law--the Lease, State Law, and possibly Federal Law.
Your lease. You should be familiar with your lease. Look to your written lease first when figuring out what your legal rights are.
If you do not have a written lease, you still can be a tenant. State law recognizes that leases can be based on verbal agreements. If your lease is for a year or less, then it does not have to be in writing. If your lease is for more than a year, then it must be in writing to be valid under South Carolina law.
State law will supplement your lease in most situations. The Residential Landlord and Tenant Act applies to all residential leases. If any term of your lease conflicts with the Residential Landlord Tenant Act, the Act controls. You can find the Act here: https://www.scstatehouse.gov/code/t27c040.php
Federal law might apply if you receive a subsidy that helps lower your rent.
The most common federal programs that might apply are the Public Housing program, the Section 8 program and the Housing Choice Voucher program, all of which are overseen by HUD (the Department of Housing and Urban Development); the Low-Income Housing Tax Credit; and the Rural Rental Assistance program overseen by USDA (the Department of Agriculture). This Classroom does not cover all of the possible rights or issues that can come up under federal law.