She had expressed to me that Covid was stressing her out, clean for years she started taking drugs and overdosed.   

I feel there is a bunch of risk with this and really just want to get it off my hands as cleanly as possible.I have a relative who owns a house free & clear 4br / 2.5ba house that is around ~250K fixed up but is currently in bad condition.  

The main things about renting to a group of inexperienced tenants is that they may not take timely rent payment seriously, they may not know the housekeeping tasks necessary to keep the rental clean, they may not know when to call about minor maintenance issues that can grow into bigger problems.  

I would need to get a hard money loan, a private loan, or POF to even contemplate attending the auction, I'm not sure whether I must submit the minimum bid if there is no competitive bidders, or whether - should I acquire the property if I would still need to file an action to quiet title in order to sell the property (even if the title report came back clean).

I have hired leasing agents, lawn care, cleaning and web/graphics design.

But if the contractor doesn't have a completely clean record, I wouldn't take on that risk and give up a large portion of your profits. 

In such cases, the local fire marshalls may have authority. some jurisidictions require tanks to be cleaned out and filled with sand or other inert substance. some require sampling. you can check with the local fire marshall without identifying the house.Again, you should find out why the tank is not used. if its because the seller no longer occupies the house, then the tank may still be able to be used. sometimes, owners decide to put a tank in the basement. you should find out if it is truly an abandoned tank or just temporarily inactive because the seller is not using the house....  

Leverage 75% LTV, buy $2M in multi-family class B/C needing lipstick to max the rents, stabilize for one year of clean operating expenses, cash-out refi, wash, rinse, repeat.

Especially considering managing the listings, bookings, supplies, cleaning, etc. 

The numbers they reported for 2019 are healthy and the owners have not been reported numbers 2020.