[Tangurena2]

Some states allow the person/org who failed to pay the taxes on time to "redeem" the debt (pay it off). So this means that for several years after you acquire the property, there is a risk that it will revert to the previous owner.

Some tax auctions are only for the right to collect the tax. In those states, you never can acquire ownership. You just get a lien.

And some tax auctions are for worthless strips of land. I've seen some that were essentially the strip of grass between a parking lot and the street. The shopping mall had a permanent easement to put a driveway through that grass (if they wanted) and there was no possible way to make ownership of that 10 foot wide (and several hundred feet long) strip of lawn to be useful. Plus, you get to pay property taxes for something you can't live on.

Tax auctions are a wild west of buyer beware.