What's kept me out of abandoned buildings around here is *who* may also be inside. Lotsa crime in New Orleans. Guess that isn't much of a concern out in the country. There's a highrise downtown (The Rault Center) that's been vacant since the 1970's when there was a fire and 8 women jumped to their deaths. Pieces of it fall onto Rampart & Gravier Streets now & then. I know someone who's been inside (legally) and they say the upper floors are gutted, walking through the lobby & ground floor is like walking into 1973. There's more vacant highrises & industrial buildings since Katrina, but I'm more wary of the bums & crackheads than the police department!
I did find my 13" XL-100 and a Heathkit W-5M amp & pre-amp in a building my old boss was taking down in '06. Also saved the 1960's recessed fluorescent light fixtures from a board room and put them in my kitchen
And an old ceramic-cased Western Union wall-mounted dialer that summoned a messenger to the place from the WU office.