I know Marshall Reddick has an office there and do private lending.

If you have a plan on where to invest it to get a better return then go for it.If not then look at ways to improve cash flow such as sub metering the electric, water and gas and arguing your property taxes down with the assessor's office (the tax assessment dispute typically takes place once or twice a year depending on the city). 

I use the Law Offices of Andrew Schultz. 

I have been speaking with a few customers and conventional loan officers lately regarding 30yr financing on investment properties and the rates I am now hearing are north of 5%.

Interest for office and retail property has cooled, but hotels are gaining interest.Investors from Asia, Europe, and Canada are expected to make the biggest contributions within the U.S. real estate market over the next few years.The survey gathered insights from 101 respondents across 19 countries.​​

So I was taking to a loan officer and he told me that I can only use the FHA loan 1 time and for me to use repeatedly I have to switch my fha loan into an conventional loan, so I was wondering what would be the pros and cons of me doing this ?

I just purchased a 4-plex, but the previous owner does not have separate addresses for each unit.For example, I pushed 123 MainStreet and I want each unit to be represented separately, 123 MainStreet Unit A.Do I need to do anything official with the post office or city?

Second, join a team (if your office has one).

Then add an office and living quarter to the Storage location to live at. 

Another option if it fit your lifestyle would be to sell your house and make a larger than normal office/home as part of your self storage location.