Great buy

"1300SF = $800-900" is reasonable.

"$30K = 1300SF,中上學區" is very hard to come by.

Either you got it for deep discount, or this is a very cheap place (but how could it support $800-900 rent?)  or it must be a rundown neighborhood, but you said 中上學區.

So things don't quite add up here...

Does it have huge HOA fee or other charges? That might explain it