Here is how It's always worked with me. If I owe them It's 7 Yrs. to sue me. If they owe me I have to sue them within 2 Yrs. or they're home free.
You are talking in both cases about business contracts. This forum,and the advice herein is for those whose debts and credit obligations are for PERSONAL not business purposes. Contract law(covering business) is VERY complex. Each State has it's own laws and particularly in the construction field has varying rules and SOL's.