It’s not a money maker and will go negative at these numbers . your forcing the numbers to rationalize the purchase .

Robertif the park is paying the water and sewer then i would look at this for at least the expense side of things, not even talking about the POHs I would offer this Number of pads x lot rent  x 60 (expense ration given that the park water and sewer is MM) for your example not including the POH, 10 lots, 350 lot rent at a 40% expense ratio 10 x 350 x 60 = 210,000 the rental income is a separate business entity, or at least it should be for the sake of purchasing the POH's the seller will most likely not agree with this as he is calculating that income from the rentals into his NOI for the parks valuation and selling price but you must not.

Patience and rationality are very important... especially early on.

The rational behind this transaction is that the seller wouldn't be able to sell their property (or would risk long days on market, selling at dramatic discount) without these updates being made.

If the logic behind your rational is sound they will consider it. 

Basic math...without rationalization.+ ARV based on sales comps (not oppinion- Profit needed (start with this at the top...or why bother)- All costs associated with Purchase (rehab, closing costs, fees, etc...)= Maximum offerDon't over complicate things.

This was my first deal and I probably over-payed and took on properties that needed more work than I could have anticipated but I made sure the rents/sale price ration was high to cover it so It hasn't wiped me out...

one thing ive learned is how dangerous rationalization is.  

As long as things are implemented in a rational fashion what this means is that non-accredited investors will be allowed to invest in offerings from syndicators by roughly the middle of the year as long as the rules aren't FUBARed somehow during the last stretch of rule-making.  

i have lenders that will lend with a 580 and the proper debt to income ration (not more than 43%) I also have lenders that give people a rough time with a 650.