Valuing Small Mobile parks/parcels

[Steve M.]

First, I apologize for the length on this, but I err on the side of too much info to start with.
I'm looking at a mobile deal to wholesale and am wanting some advice on best practice to find the ARV. It's somewhat of a mixed bag, thus the questions.

Details:
22 Total Mobile units ranging from 1br/1ba to 3br/2ba.
AP: $139,000

Here's the mix:
3 units on 1/4 acre owned land & mobiles.
6 units on 1/2 acre owned land & mobiles.
For both, $350/mo water, $74/mo trash, $800/yr taxes.
Avg $300 per unit rent for easiness ($2700 GMR) sake.
Seller says appraised 2yrs ago for $57k/74k respectively and he owes $80k roughly for both parcels on one note (basically says he owns all 22 homes outright, lien is against land parcels). Both of these small "parks" are inside city limits.

Other 13 units are scattered between 3 other small parks. I'm sorry, but I don't know what the total lots in each are, but the largest is about 20 lots. 2 are rural outside city limits, one is inside city limits. Avg rents again are about $300/unit (total monthly $3900). The lot rent for all 13 of these between all the parks is $1,080 mo/ $12,960 annual.

Leases are month-to-month, no written agreement. Property manager/rent collector/maintenance person lives in one of the trailers for free rent (seller lives 30-45 minutes away from location). I met her, prop mgr, today just by chance doing some repairs to one of the trailers. Since she's rent-free, deduct $300 mon/$3600 Annual rent from totals for an annual gross rent of $75,600 potential.

I have not done thorough inspections on any of these trailers, but from the looks by driving by, most are probably 70's or 80's models worth anywhere from $1k-3k depending on the size and age. All seem to be in fairly solid shape. Not pretty on the outside, but the one I looked at seemed solid structurally with no sagging, rotting wood or visible leaks inside.

The area I'm in has a median income of about $26k, so there is high demand for this level of rent/payments. I've done some rental analysis at $120k offer, 10% down, seller carrying the note at 8% for 2 yrs max with about another $10k in other acquisition cost contingencies (initial repairs, fee to me, closing costs, attorney's fees, DMV transfer, etc). I've also figured in property mgmnt @ 10% just in case the current tenant moves on who is doing that for free basically.

I would like to try to wholesale this, but the seller isn't in dire straits, just wants to be done with the mgmnt of it. I have 2 investors that I've peaked interest with, but I want to make sure I'm doing my numbers right and not missing something.

Does anybody have a good formula for doing an income valuation approach on the parks/parcels that are owned. I can't really use land comps since these are developed park lots, but there are also not any MH park sales that I can have a realtor lookup here either. So, to me best way is an income valuation approach, which I'm thinking is where the appraised values came from 2 yrs ago.

At $120k offer, $22k cash in, I'm getting a GRM of 1.59, Cap Rate of 34% and ROI of 143%. Even at the full offer of $139k, I'm still pulling very good numbers.

Any questions, thoughts on how to best value this to an end-investor?

Sorry for the book again.