Federal Tax Lien search on tax deed properties

[Jenna Pedersen]

I'm looking to purchase some tax deeds from my county in Oklahoma and am currently working through my due diligence. However, I am getting hung up on the federal liens. Where do I need to search for these? It is my understanding that once purchased, the tax deed will wipe out other things such as the mortgage. However, I know that some things supersede and need to be paid after the purchase. I just want to be sure I don't miss anything and get stuck with a bad deal. Thanks for your help! Please let me know if I am misunderstanding any of this as I am new to REI.