I agree that QuickBooks is user friendly. However, make sure that the bank you open your business account at is able to support automatic downloads into QuickBooks. We ran into an issue with this AND it was doubly difficult because we also use a Mac, not a PC. Just something to think about! Because we are on Mac, and also we're a construction company (so our accounting is project-by-project and pretty straightforward, with no direct payroll involved), I am using iBank and it's working well for me.
At my last job, I was a commercial property manager and we used Yardi for accounting and tracking the properties. It is made specifically for property management. Our version was pretty sprawling (lease accounting, Landlord accounting, insurance tracking, property maintenance tracking, lease agreement tracking, CAM billing, etc etc). As such, it was not the easiest program to learn to use, but it did absolutely everything we needed it to do, even down to cutting checks. You may want to look into it and see if that's a viable option for you.
Good luck with your new business!