If I don't maintain the foundation, the $$$ spent on the aforementioned renovation could all be ruined (over time). 

Can you maintain expenses and pay your investors back?

Since that time I have made all the mortgage payments and maintained the home. 

I am starting a business which involves offering residential services to people in the form of lawn care, house cleaning, light repairs (drywall, painting, fixing a single fence post, etc...) and basically just doing jobs that help maintain and upkeep properties.

I'm not sure how difficult/costly it would be to form the LLC so I don't know if any hassle in forming and maintaining the LLC would be worth it (considering the only property I own is just my primary residence). 

This will be a personal/business decision but if they have been good tenants, pay on-time, and keep the property maintained then you should consider the price of your relationship. 

I still have my license just to maintain the opportunity to jump back in if I desire.I am going back to school for a BBA in Real Estate.

Do you(the broker) maintain a copy of my leads if I leave?

- If I use a fund to purchase properties and intend to pay dividends out to the investors of the fund, do they gain equity in the company or can I maintain 100% equity and simply pay them based on their equitable contribution to the fund?

On the other hand, keep in mind that there are costs associated with maintaining an LLC (such as the $800 annual franchise tax in California).2.