House rent or lot rent?

I purchased a park about one year ago with 20 park owned mobile homes on it. The seller is holding the note at 4% interest. It is amortized over 30 years with a balloon at 10 with an option to refi for 10 additional years at the same rate or pay off. I had to put nothing down on this. The houses are primarily late 70’s early 80 models and often need repairs. I keep about 80% occupancy at $300 a month. Would it be benficial for me to keep going at this rate or to sell the homes and rent lots for $125 a month??? If the tenants were to ever leave with the homes I have access to several repos and my dad is in the set-up and moving business so I only have expense of materials on the set-up. I am 23 years old and a fulltime firefighter so this is just a secondary retirement for me so I want to insure that I take the right steps in making it a successful venture. Thanks for any and all input.