A couple that is sueing me is very shady.Where do I go 2 get info about them if there has been past problems?

originally they wanted some money to do a project that was damaged during the last heavy winter. a month later they wanted the full purchase price of the house and an additional $65,000. They have not backed down after trying to work with them and tell them there is nothing wrong with the house. They were told everything and even was given a extra $12,000 2 pave a driveway. There are 4 areas that are a bit shady: 1 is the money they are asking for and it rising so quickly without any new or preexisting damage, 2 he is a civillian in the military and was transferred here 2 sacramento area a year ago could he be getting transferred?, 3 the wife changed her last name back 2 her maiden in the past few months, are they getting a divorce and need 2 sell the house off quick?,4 they could be over their head wih the house payments, they have an interest only loan and it has been a year? don't know where 2 go 2 find out if there has been a problem before or if they are getitng a divorce. Help!!