What is the best way to start your own personal et management company?

I am considering starting an "et management company", most likely under a LLC status. But I want it to be my own ets. I would like to purchase (for rent) small homes, condos and/or townhouses and then eventually diversify the portfolio to mutual funds, stocks, bonds, franchises, etc. Adding my own money and any profits from the rentals. Is it a good idea to put it under an LLC? Would this even be considered an et management company? An advice or tips is appreciated.