You will make more money on appreciation when you sell your property than you likely will from the monthly cash flow.  

Subdivisions of build to sell are favorable to local SFR landlords because more rooftops means more retail and dining, which makes a more desirable rental area. 

Robert Lane, best real estate agent so far I Know Keep or sell comes down to performance of the investment.

If you have family get them involved...sell FB marketplace and eBay for a year and they can do that from home.   

Ideally a HELOC is used for less then a  year project where you can refi or sell to pay back the HELOC. 5 years is a long time, things can happen and if you reduce the cashflow on both properties you'll be increasing the risk and having thinner margins.

In my take, I'd buy Pine (which is 5/2 2700sq ft) than Byrd (3/2 1832sq ft)- But the price differences may be due to desirability of neighbourhoods (someone takes about crime in Niagara NY)Also, 353 Buffalo Ave, Niagara Falls NY 14303 (5/4,5 3255sq ft) is selling as an AirBnB for $749,900 on Rabbu> Ann rev @ $63,755 and gross yield at 8.5%.

When you go to sell, Montvale requires a certificate of occupancy so this issue has to be resolved in advance of a sale.Although I am not a lender, I assume you will not be approved for an owner-occupied mortgage on 5-units if it is a legal 4-unit without some type of mortgage fraud whether in reported rents, units, or another legal document or representation (very very large issue from a legal perspective with multiple arrests in the last year for anyone playing fast and loose).As far as the DCA, I would recommend coordinating your work with the city with the DCA.

You'll be selling a house that is worth what comps say it is worth. 

The seller can often sell a property that can not otherwise be sold, financed, or sold for enough to pay off existing mortgage or obtain a higher price by selling Sub To, or Sub To wrap/owner finance.  

But you should be doing the number crunching yourself and not rely on someone else especially the person selling you the property. ✌️ (and don’t forget to calculate short term capital gains tax - that’s why I prefer passive income over flipping)