If the home you are looking at is owned by a finance company then the resident/tenant is the registered owner and they would have to sign off as RO and asign it to you which most lenders won't allow without qualifying you as the new owner.
If the resident/tenant is the registered and legal owner and there is no lender involved they would then have to designate you as the registed owner in most cases. You're always wise to speak directly to the park owner so you will know first hand what your options may be.
If it's a MH in a resident owned condo conversion, subdivision or planned unit development (PUD) and the home is owned by the resident that's an entirely different story as long as there are no HOA rules and regs that govern how long you can stay. Some resident owned communities have 6 month to 1 year maximum stay requirements. The reason being they don't want a lot of long term renters as they would prefer the owner/resident be the primary resident.
Just make sure you get all this information disclosed upfront before you put any money into the pot. Good luck.
I do know of one that is coming up in a couple of weeks. Maybe sooner. It is near Imperial and La Palma. Anaheim Hills/Yorba Linda area. Gated community.
You can call if you are interested.
Prudential CA Realty
dre # 898302