Make many offers below asking.3.  

They offer better economies of scale and tend to be more manageable as you grow your portfolio.

Offering a rent-free period helps the seller stabilize, but what happens if they still can't afford rent when the time comes?

Both investments can offer tax benefits, but real estate typically has the edge.

Why not use the higher end of the estimate and once you are serious about putting in an offer contact your broker then?

Id keep looking if it was not an approved short sale ( even an approved short sale takes a very very long time and theres no guarantee that you will even close on the house after months of waiting). q1)There are plenty of non traditional lenders that could offer you construction financing if the numbers make sense but it will cost you with points and a higher rate.

If you really want to get rid of them, sweeten the pot by offering to return their deposit after you verify the unit is empty with no damages. 

Build savings through side hustles like flipping cars or offering handyman services.

I'm just going to offer my opinion on Arbitrage in general.

The key is to offer something different to the other homes, and be an attentive host, to get good reviews to boost OTA (Airbnb/vrbo) rankings.