This should increase my cashflow overtime.

The home is in great condition and in a great community.  

Here are the key data points:Park info  Located in Alabama61 lots25 owner occupied homes18 park owned homes (14 currently rented; 4 currently being repaired and should be rented soon)18 vacant lotsAvg lot rent - $160 (unknown what the market rate is but it doesn't sound like there has been a rent increase in at least a year, maybe more)Avg POH rent - $400Expense ratio - seller claims 26% but I'm estimating 35% for the lots and 50% for the POH'sCity water - individually meteredSeptic - good condition (allegedly); a couple were pumped last year, none this year (no lagoon thank heavens)Seller claims gross income $130k, expenses $30k, and NOI $100kI calculated gross income of ~$135k, expenses of $60k (55% on POH and 35% on lot rentals), and NOI of $75kOther infoMom & pop seller, but park is listed with a brokerPark has been on the market for > 3 years (recent price reduction)Greater metro area stats look goodPopulation = 115kMedian home price = $105kUnemployment < 8%Household income > $40kHousing vacancy ~ 15%Closest Walmart is 7 miles awayFreeway is 1.5 miles awayNumbersMy valuation is coming out about $80k-$100k under the seller's asking priceWith conventional financing I'd be hoping for a purchase price of $500k, $100k down @ 6% over 20 years (not sure if this is plausible or not)Assuming that financing, I'm expecting net cash flow of $40k (after debt service)Upside potential is in raising rent and filling the 18 vacant lotsFollowing the same assumptions above, raising rent $50 (if the market supports it) would change NOI to ~$90k and net cash flow of just over $50kFilling the vacant lots could potentially increase gross rent up to somewhere between $150k-$200k, depending on what the appropriate occupancy rate is for the areaWithout verifying any of the above information (haven't offered anything yet so there's a lot of DD left to do), the deal seems to make sense. 

Below is what you need to know that underwriting and programs guidelines don't tell you when considering a 223(f) apartment loan.AdvantagesHighest LTV in the marketEliminate refinance and interest rate risk with fixed rate terms up to 35 yearsLow fixed rates based on GNMA securitiesNon-recourse and assumable - makes for a great exit strategy especially in a rising rate environmentNo defined financial capacity requirementsNo geographic restrictionsNo minimum population requirementsSupplemental financing availableDisadvantagesLonger processing times - 120 days at a minimum (6-9 months is typical)Higher fees - HUD and FHA fees add to the overall cost of the loanMortgage Insurance Premiums (MIP) - Initial and annual premiumsAnnual audited operating statements requiredReplacement reserve escrows requiredHUD property inspections requiredOwner distribution restrictions and Cash out restrictions 2x a yearProperty condition is important to HUD, both during initial underwriting and over the life of the loan.

Most times, these parks try to keep their tenants and may have issues refilling the lots due to market demand and/or condition of the park.

One aspect that most people do not consider, is the increased water and sewer usage bills due to the laundry.

It is in bad condition needs a lot of work.  

She knows that rent will be increasing, but she can't afford too much more.

-will Contractor bids increase and will take longer to complete remodels due to high demand for labor?

Unless it is pretty standard in your all's area for a tenant to pay an agent's commission, I doubt there would be many (if any) people willing to rent the apartment under those conditions.