Most contract and consumer-protection questions come down to state law, and the answer genuinely changes at the border. A security-deposit return deadline, a late-fee cap, whether a non-compete is even enforceable, how much notice a landlord must give before raising rent — each of these is set by the state you are in, not by a single national rule. That is why a clause that is perfectly standard in one lease can be unenforceable a state away.
These quick cards summarize the rules people look up most — security deposits, non-competes, early lease termination, prepayment penalties, and NDA enforceability — in plain language, drawn from verified statutes with source links so you can read the primary text yourself. Pick your state and the topic, get the short version, then compare it against your own document. The Main AI app can take the next step: read your actual lease, offer, or notice and tell you where it lines up with your state's rules and where it does not.
These summaries are general information, not legal advice. State rules change; check the linked statute or a qualified attorney for anything that affects a decision.