@Taylor Cook - Lots of good information from all of the posters. As a bookkeeper here is what I tell potential clients. Its time to get a bookkeeper when it is costing you.... the cost is time away from family or finding the next deal no matter what field you are in.
A good bookkeeper will take a lot of your plate, but as mentioned it will be hard with multiple properties to get it all of your plate.
Like anything when you hire a professional and thats all they do, they will be able to provide more insite in to bookkeeping and your industry that the ROI is way more than what you are paying them.
As for who should be doing your books, I am a big believer that you should have multiple people looking at your books. For example, don't have your CPA firm do your books, why because if there is a mistake they won't catch it. Mistakes happen, more eyes on the books hopefully will catch those mistakes, and bookkeeping and tax mistakes cost money.
Can you do your books yourself? Absolutely. Is bookkeeping hard? Not for some people.
Happy to talk to you or anyone else about bookkeeping. Another great bookkeeper in this group is @Max Emory to talk to.
Hope that helps.