court house steps and tax lien -

I have done many auction.com/hubzu/xomne purchases. I want to dip my toe into court house steps because I have purchased some of my flips from these guys and I buy many properties as/is with no access inside on auction sites.

In my research it was not clear - Do I need to have a title search done on these properties or can expect them to be free/clear of tax liens and clear title on transfer?