I agree with Drew to add at least 10% on top of your construction bid. 

If the agent/listing disclosed it needs work, selling as-is but that you likely wouldn’t win bid with an inspection contingency, then you decided not to have it inspected, that’s a different, hard lesson.

Your best bet is to consult with a few contractors to get some bids and go from there. 

I would get a few bids first from a contractor and then talk to a realtor/appraiser to see what the numbers look like 

There were many bids, and hours of discussion over how to properly proceed once all of this had come to light.  

There's a lot of competition for both SFHs and MFs in GR, but SFH owners NEED a place to live and I find I cannot and don't want to compete with them in a bidding war, as I simply can't make my numbers work.Buy a duplex and Owner Occupy the one side.  

Bring a local GC with you when you go so they can get a rough idea of a bid for renovation.

So if the lien amount is $1000 and you bid and win it at $1,100.   

.- at Home Depot always aks for better pricing at their bid room.

(believe me, it was much more painful move out and sell our last homes in Alaska than to move out of rentals)A couple of BiggerPockets podcast guests have stated that they don't own a primary residence -- they invest where the returns are good and live where they want -- for as long as they want -- and use the rental income to pay rent.While I was still a Dave Ramsey, no-debt adherent, I bid (and won) some cheap tax deeds.