It is more common to compare total sf.

Forget the name is such service but it would be worth it compared to forking over double the deposit.

An odd question, but what would a responsible RE investors consider to be a good % of the value (market price, not equity) of your primary residence compared to their total net worth?  

I can give you very high level calculation to understand both scenario...Lets say you buy 100K house with 1000 rent... lets compare all cash against leverage...All cash InvestmentYearly return = 12000 (Rent) + 2000 (Appreciation) - 3000 (Tax + Insurance + Capex) = 11000 = 11%LeverageYearly Return = 1000 (Rent Cash flow) + 2000 (Appreciation) + 3000 (Amortization) = 6000 = 6%Now when you leverage investment at 20%, you can buy 5 house from 100KYearly Return of 5 Houses = 6000 X 5 = 30000 = 30%There are more tax benefit in this deal also as your positive cashflow is lower...If you are planning to buy multiple houses, Leverage is always better...

Can you verify the seller pro forma against prior year actuals? 

Then if you see a Demo order recorded on title by a judge in the past you will know that must be removed prior to any lender agreeing to put a mortgage lien on the property.

Or could this be done prior to selling? 

Understand the fees involved and calculate the total cost for an entire year of management so you can compare the different managers.

I just want examples and context to learn from so I can then go out and compare what I see to what I've learned.

When temperatures drop to a point where the heat pump can no longer do its job (i.e. somewhere below -13F to -20F) - perhaps even prior to that point when COP factor on the heat pump drops below a pre-determined threshold - the existing furnace would fire as the stage 2 heat source.If your oil furnaces are much more than 20-years old, their efficiency will likely be less than 75%.