Deed sale parcel with a city demolition lien and something that looks like a federal tax lien

Looking at an upcoming deed sale in a county I know the construction side of well. Parcel is a 1940s balloon-frame house, opening bid $9,400, which is four years of taxes plus fees. I've walked past it, roof sheathing is visibly gone over the rear addition and the porch is separating. My scope guess is $65k to $80k assuming the framing is salvageable, and comparable finished houses on that street run about $140k.

What I can't resolve is the encumbrances. The city has a recorded nuisance abatement and demolition lien for about $18,400. There's also an entry in the index that looks like a federal tax lien against the owner. My understanding is a tax deed wipes most private liens in that state but municipal claims can survive, and the federal government has a redemption window after the sale, which would mean I could sink money into stabilization and then be bought out at what I paid plus a statutory rate.

Three things I'd want to know before I register:

Whether a demolition lien recorded by the city survives a tax deed in a state where the deed is issued by the county, since they're different taxing bodies.

Whether title insurers in that state will write a policy on a tax deed at all before a quiet title action, and what a quiet title runs when the former owner is deceased and heirs are unlocated. I've seen $2,500 quoted and I've also seen $9k.

Whether an open demolition order transfers as an obligation to the new owner, meaning I'd be buying a countdown clock rather than a house.

I know the answers vary by state and I'll be paying a real estate attorney there to read the statutes before I bid. What I'm after is which of these three usually turns out to be the deal killer, so I know where to spend the consult time.