Legal Question in Real Estate Law in Virginia

Generally speaking, if both sides have signed the same contract, and it does not require a third party (it's just between buyer and seller, as is typical), that is a binding contract (assuming other requirements are met such as legal capacity (are the parties of legal age, for example); definiteness (is there enough detail to make it clear what is being agreed), etc. If there is a real issue about a specific contract, see a lawyer.