Start with The Millionaire Real Estate Investor and The Ultimate Beginner's Guide to Real Estate Investing, which you can find here: https://www.biggerpockets.com/guides

The receipts will serve as ultimate proof for an audit.Your data in QuickBooks should be accurate as long as you are reconciling to a bank statement each month and categorizing appropriately.

Hi @Jimmy Samai, ultimately the decision is up to you on whether or not you want to try out the course.

How would all these people survive?

Ultimately I wanted a vehicle that I could have control over to provide income to augment or bridge me into retirement (which isn't for 15 years).

Final approval will ultimately be up to the investor.There are other/additional factors as well.

Welcome to BP @Valerie Lopez  Since you are so new I suggest you check out the Ultimate Free Beginners Guide

(If you used the CAR Estoppel Certificate form, it asks whether the tenant is currently in default under the terms of the lease.)Ultimately, you own the property now so as @Jack Edgar jr suggested, just make contact with the tenant and explain you're the new owner and the new process for paying rent. 

Have you read The Ultimate Beginner’s Guide to Real Estate Investing? 

I’m not trying to discount their desirability as rentals but you’re ultimately in this to make money right?