Although it may sound easy to recommend an agreement be written versus oral, sometimes time does not allow this to happen and does not allow every agreed upon aspect included in the contract. For instance, when a quick decision needs to be made an oral agreement may suffice. However, if details are left out for any reason, both parties will have a hard time disputing it in a courtroom.
I don’t believe verbal agreements are solid. People can change their mind and lie in court and then it is simply their reputation against yours. I always believe a signed and notarized agreement is one of the best agreements that will hold up in a court of law.