Because I also own and buy actively, I also have the proven vendors that further save my clients money from insurance, landscaping, pest control, pool care, and handymen/hvac/plumbing/electrical.With all that in mind, there's a few different categories of property you can buy that maximize their returns. 

Connect with the Amish and Mennonite communities.

Hi all, we are looking to replace our current apt building access system vendor.

Evolve does have vendor and professional service  referrals in the area of your home should you need it, but I found networking with other investors gave a better result. 

You can invoice them monthly and collect like any other vendor. 

@Derek Morrison  Look at multiple vendors and different options. 

Perform the same task in each app to ensure a fair comparison.Load a property with pictures and details.Market that property.See what your marketing looks like from the public's perspective.Submit a fake application to see how easy the process is.Run a credit/screening report on yourself.Enter a maintenance request, assign a vendor, and attach a fake invoice.Enter charges to the tenant's ledger.Enter recurring charges and automatic late fees.Sign documents electronically.Run owner reports.After testing a few apps, one should clearly stand out.

I have a CPA firm I use personally - but I still compile my receipts, and organize them - cost, date, project, purpose, vendor etc.

And keep in mind all affiliated operational expenses such as all the vendors, as those costs go up..... 

I run a monthly REI Meetup in Niceville, where you can connect with some great local investors and vendors.