I service some strip malls in my area for an out-of-state management service. They always pay within 3 to 4 wks and they never question the bill. They're a pleasure to work for. Same thing with another management company from No. Jersey (about an hour away). I service one building for them about 5 minutes from my shop. They call me when they need something, I send a bill when the job is done, and they pay me within 10 days.
I've also worked for several other management companies in the past. They've generally been slow to pay and sometimes difficult to deal with, though I've never been burned. Make sure you settle on a price before you start the work. Make sure you know the terms and who to send the bill to. I've had payment withheld because I sent it to the wrong office, or because they didn't have my COI or W9. They're not loyal either. I'd work for them once or twice and then they wouldn't call me again because they found someone cheaper. Or they'll call me out of the blue 2 or 3 years later. I'm ok with it either way because I know who & what I'm dealing with.