As soon as possible. Once the lawyer is involved, he/she can start working to protect the purchaser's interests. When it comes to buying and selling real estate, "the devil is in the details." All too often, a fact or item incorrectly set out or completely overlooked in the original sale contract develops into a legal issue or matter of dispute between the buyer and seller. Such problems can be avoided by obtaining legal advice from a real estate lawyer early on in the process.