Thoughts on this combination deal? Two property package

[Joseph Matarazzo]

Hello BP community,

I have the following deal which I could use some advice on. Seller is selling a 5 bed, 2 bath, 1400SF house for $489,000. It is being sold with an empty lot of land next to it, which is listed for $350,000 and they are asking for cash for the land. The two properties must be bought together. 

The house: Running the numbers: I could purchase for the full asking price of $489,000. 20% down. The property would cash flow +$1,400/month on average in a short term rental market (Beach town). The CoC return is 16%. The 50% rule has a cash flow of +$1,900. Obviously this is a no brainer, good deal.

What makes the overall deal risky is that the lot next door is an irregular lot. I am not sure it is the right shape/big enough to build on. If it is able to be build on, I can spec build a house and sell it for profit. (I would be happy to share these numbers as well if anyone wants to see them).  If it is NOT able to be built on, then it is unusable. 

What do you all think? My plan is to call the zoning office when they open tomorrow (today is a holiday) and asking about the empty lot and its dimensions/required setbacks. Hopefully there is good news from this call.  But if the property is unusable, do you think that  sinks the deal? Would you consider buying both properties just to get the cash flow from the one property? It would bring the cash flow down significantly, but it would still be positive a couple hundred dollars.