I do use both. I have used QB for 20 years as a bookkeeper for different companies including one that handled commercial Real Estate tenants so I already know how to use it, and I use it for my other business so it's practically a "no brainer" that I'm going to use it for REI.
The class tracking feature allows me so much flexibility in how I can see my data. For example, I have 4 rentals (4 SFH). 3 in Rockford, IL & 1 in Beloit, WI. I can run a P&L and see how they are all doing combined and individually, or how are just the IL properties doing... OK maybe I'm a bit of a bookkeeping nerd :-)
I use Buildium for building my listings, applicant screening, and tenant payments. My husband/partner can log on from anywhere and see tenant payments and charges and see basic income statements. It also tracks my leases and move in/out dates. I don't put all my invoices in it because it would be (for me) cumbersome to try and use it as a QB replacement, probably because I've used it for so long already.
I guess it's pricey ($36 monthly) for Buildium with only 4 rentals but I think it's worth it.
