If you want to get that big you have to find a way to remove yourself as the bottleneck and have systems in place so that things run without you in the picture.The things that I find bogging us down, preventing us from doing the important things like finding money and deals, and that I plan to hire out are:-Day to day phone calls about Maintenance, Rent payments, Lease questions-Listing and showing properties-Drafting & signing leases-Generating and mailing/delivering 7 day notices-Entering bookkeeping into Buildium-Water billing-Occasional Bank Deposits-Occasional other errands like dropping off checks or materials to contractorsI think the first one will be the toughest, as I never know what will be on the other end of the phone line and many questions I get require discretion and careful handling.

Ask him for his rent roll/bookkeeping for the past year or 2 to verify that these tenants are actually paying this rent.

Payroll, bookkeeping, etc can mostly be done remotely.Here is a great list of questions to ask a potential accountant:http://www.biggerpockets.com/forums/51/topics/70447-questions-to-ask-a-cpaAlso check out the www.NAEA.org page in your search.

Things certainly could change, but for now I hope to acquire, improve, and hold one or two properties per year until I have 8 - 10+ good rentals working for us.I have settled on Online vs Desktop / Pro because I want the ability to upload receipts wherever I happen to be with the mobile app, and since my wife and I will be sharing the bookkeeping responsibilities.  

Payroll, bookkeeping, etc can mostly be done remotely.Here is a great list of questions to ask a potential accountant:http://www.biggerpockets.com/forums/51/topics/70447-questions-to-ask-a-cpaAlso check out the www.NAEA.org page in your search.

I hired an accountant that handles most of my bookkeeping.

If he is the investor should he also be the accountant/book keeper/ account payable? 

I use the bookkeeping software Stessa.

stessa is free and BP sponsored, i use bench for my bookkeepers

There's plenty of responsibilities that need divvied up- leasing and managing the tenants and maintenance issues that come up, bookkeeping/accounting/paying the bills, etc.