Probate, wills, and clear deeds

[Michael Bradford]

Advice requested. Situation: I have a seller who's common law wife has passed. She left him the house in her will. The county assessor's office has her listed as the owner, but in the address it says "C/O 'his name'. He does not know the location of the original deed. Will there be a problem with the deed if I make an offer on this property and if so, how can this situation be corrected?