For those of you who are seasoned investors, I would greatly appreciate any recommendations you may have.

I recommend buy a primary home where you want and invest where the numbers make sense.

If you want to go further, you can use a service like Safely or AutoHost to run background checks.For payments, I’d recommend using a platform like Stripe or Square—they’re secure and easy to set up.

Any recommendations on the most efficient way to track your time when classified as a real estate professional?

@David R Pustelnik recommend you first focus on raising the rent for the first time in 10 years.By the way, how much have your property taxes and home insurance gone up since this tenant moved in?

@John McKee what would be some companies/funds you would recommend?

Could you please recommend any local real estate agents?

I would recommend considering conventional financing until you reach Fannie Mae's limit of 10 properties, then consider either a portfolio loan, and start your race to 10 again, or look at DSCR at that time. 

For example, a property in San Diego may lose $500 per month ($6,000 per year) but gain $60,000 per year in value, making it worthwhile to "lose" money each month in exchange for long-term gains.I recommend you start with BiggerPockets Ultimate Beginners Guide (free).

Any recommendations for free tools to do market research?