Jana, all mortgage companies will require a clear title to the property you're using as collateral. If you're obtaining a mortgage, the lender will take care of this for you.

If you're paying with cash, then absolutely be sure to hire a realy good title company.

Having a realtor involved can help with the sales contract-- whether paying with cash or not. I personally would never attempt to buy a house without a realtor representing me-- and I do mean representing me, not the one representing the seller.

Hope this helps.

As another Realtor said "a title search" on the property is the best way to find out. I hope you're working with a Realtor who can advise you and provide valuable information. There are some enhanced title policies as well that provide extra coverage in case something happens after the search. You will need in this case to contact a Title company. The contracts we use also allow us to write small clauses for the consumer's protection. Hope this helps!

Kind of confused on second part of your question, I hope this is the answer you are looking for. A title search on the property is how you find out about existing liens. The sales agreement should have contingencies in regards to being able to back out of a contract if any liens pop up after you put an offer in.