This post contains spoilers for Resident Evil 0.
There's a copule of things about the locations in RE 0 and RE 2 that doesn't add up
Behind the Management Training Facility there's the church that's avobe Marcus' laboratory, and has a station for the Sky Tram. When Rebecca enters it and travels to another station, she ends up in the Umbrella Factory, that's avobe the Raccoon City Underground Research Facility. When she takes the elevator down, she ends up in the underground facility, which has an elevator that takes you to the basement of the training facility. So, if it was all conected by walking distance, ho much did the tram travel? A couple of meters? Besides, if the Factory was a façade for the underground facility, it doesn't make much sense putting a large mansion right next to it.
And also, if it was all so close, how is it that the explosion that completely destroyed the training facility and the water treatment plant didn't do any harm to the underground facility or the factory?
I don't know, maybe I missed something...