A low income Habitat for Humanity family has been unwillingly deeded a very run-down house in a blighted area of a large Midwestern city. The house is uninhabitable and they would like to abandon it rather than have to pay property taxes out of their limited income. Can they just walk away without negative impact?

Do you mean they have been deeded the house, they now own the property? If they don't pay taxes that will go on their credit report.

They could have refused to accept it under the terms of the will - if this is an estate. Is it too late to do that?

If they own the house ( already have the deed) the house will be sold for taxes ( at some point)

They should merely try and sell it for what they can get, a few 1000 is better than nothing