I'm wanting to offer my guests a discount for extending their stay, or coming in a day earlier, to help cover one night gaps in my calendar.

It typically takes about 15 minutes to change one out.

Maybe your offer will be more attractive to others.I'm not poo-pooing your idea, but I am skeptical enough that I won't ask for an analysis of a particular market. 

FHA offers a 3.5% down payment option up to 4 units and Fannie Mae offers a 5% down option.If those down payments are too high based on the purchase price you can again, use a DPA program.

HVAC repairs today are typically pretty easy to diagnose. 

I had walked the property and told him he was crazy for not making an offer.

With a sellout of $1.3million, deducting the closing costs and hard money lending interests these people typically have. the builder will be left with about $80K profit.

You will get the typical pitch for a mentorship program at the end.

You should located a Commercial Broker in your area to pull Comps for you to determine your offer price. 

:Class A Properties:Cashflow vs Appreciation: Typically, 3-5 years for positive cashflow, but you get highest relative rent & value appreciation.Vacancy Est: Historically 10%, 5% the more recent norm.Tenant Pool: Majority will have FICO scores of 680+, zero evictions in last 7 years.Class B Properties:Cashflow vs Appreciation: Typically, decent amount of relative rent & value appreciation.Vacancy Est: Historically 10%, 5% should be applied only if proper research done to support.Tenant Pool: Majority will have FICO scores of 620-680, some blemishes, but should have no evictions in last 5 yearsClass C Properties:Cashflow vs Appreciation: Typically, high cashflow and at the lower end of relative rent & value appreciation.