Also your permitting process, type or land, grade of land, if underpinning is required will all play a factor into your cost. 

I've included an example below to help illustrate this.So different lenders have different rates (which do vary even for DSCR loans) but these are factors they all consider.See example below:DSCR < 1Principal + Interest = $1,700Taxes = $350, Insurance = $100, Association Dues = $50Total PITIA = $2200Rent = $2000DSCR = Rent/PITIA = 2000/2200 = 0.91Since the DSCR is 0.91, we know the expenses are greater than the income of the property.DSCR >1Principal + Interest = $1,500Taxes = $250, Insurance = $100, Association Dues = $25Total PITIA = $1875 Rent = $2300DSCR = Rent/PITIA = 2300/1875 = 1.23If a purchase, you also generally need reserves / savings to show you have 3-6 month payments of PITIA (principal / interest (mortgage payment), property taxes and insurance and HOA (if applicable).

In evaluating seller financed notes, there is always a balance between redeeming and non-redeeming factors. 

Definitely worth factoring into your strategy, though

I understand there are some other factors I glossed over like gaining the approval of the first seller to switch collateral and the lien in second position, gaining approval of the second seller to put a second position lien below the big loan, and scheduling the sale of the first property to coincide with the purchase of the second property.

You clearly have factored this in already.

.• That the grantor/mortgagor was insolvent at the time of the execution of the deed.An estoppel affidavit (executed and acknowledged by the grantor/mortgagor, attesting to the fairness of the transaction, the consideration exchanged, the value of the property, and other factors showing an intention to make a genuine transfer) or a recital (inserted directly in the deed) are supporting documents used to forestall challenges to these transactions.State law and local title standards must be consulted in regard to the consideration and treatment of deeds in lieu of foreclosure.What a GREAT post!   

I'm sure they are out there but this is just a rule of thumb and I would rather use J Scott's approach when he analyses deals outlined in his book.You factor in your desired profit as a cost and you work backwards.

* What are some factors to consider when identifying these hot spots?

Recently, a lot of the market factors that kept people away, are the same that are drawing attention.