I was investing in mobile homes 15 - 20 ish years ago when you could still owner finance them. That was prior to me owning parks. So I can really only speak to how I lease option in my parks, or lease in my parks. I do have some individuals that I have allowed to have investment homes in my parks and they lease the homes, and just pay me space rent.
If I were going to get into the mobile home leasing business I would present myself to park owners as a solver of problems for them. most park owners, myself included, really do not want to mess with renting homes, we just want to collect our space rent. Home rentals and park ownership are really two businesses, and they require differing skill sets and different employee tracts. This is how I got pretty big in buying and selling mobile homes, the park owners would give me the abandoned homes and I would fix them up and sell them. At one point I had 50 homes I was financing in one park alone. In short, parks would give me like one home, and a few weeks later I would have it fixed up and ready to sell. Within a few days it would be sold, and then the park would give me a list of all of the abandoned homes and tell me which one I wanted next. So- how does that math work. If I was the person doing the fix and leasing, I would make an agreement with the owner you owe no space rent for a reasonable amount of time to renovate the home. Call that- 60 days. I would also have an agreement the owners manager could show your home, and maybe you 'spiff' the manager once it sells. Also- no space rent while the home is on the market- but only if the home is really marketed. Also- an agreement for reduced or no space rent for a reasonable amount of time if the home rental goes bad. A deal like this is win - win. The park owner needs to approve the renter, and so do you as the mobile home owner. A home will probably average in fix up costs a few thousand - 4 or 5 thousand to fix up. Some will be more if they are really trashed. If you get the home free and have no or very low carrying costs, you should at the very least be in a 50% cash on and in some cases more like 100%. Overall though, if the homes go bad every few years and you have to fix them up again, you will have another outlay of cash. Call it on average $2,000. So your returns lower to 25 - 75% depending on the market, labor costs etc...
This only works if you are very efficient. I ran a full time crew (3 people) and had months of work in the pipeline. Once a established home went bad I had it back ready right away, maybe a week tops. We used the same stuff in every home so there was never a discussion on what carpet to buy or fixtures to use. If you are going to play this game you must know material costs and what a job is worth. I can walk through a home and know the amount of time within maybe 4-8 hours and the material costs off the top of my head.
Here are the warnings-
you MUST have a win win deal with the park owners
you MUST have the managers on board, showing your homes
you MUST understand the rehab side- if you leave it too contractors you will loose your shirt
you MUST be true to your word, if you say something to a park owner- follow through