A simple GIM scenario using round numbers:
wash A needs no upgrades and does 100K/year revenue Expenses are at 40% of gross, which is low for most SS/IBAs, especially in northern climates
That leaves 60K to make the payment and income
Paying 3X gross(300,000) would be a 20% return on cash
Paying 4X gross (400,000) is a 15% return on cash
Paying 5X would (500,00)be a 12% return
If you paid 4X and put 30% down (120,000) and financed the balance (280K) for fifteen years at 6%, the annual debt service would be about 28K per year, leaving with you 32K net income. But I've had income swings of up to 20% in various years due mainly to weather. Do the numbers on a 80K gross year and the income after debt service drops to a level where you wish you worked as a wal-mart greeter so you could make the same money and turn your damn phone off at night
The real danger is if everything goes well for ten years, then competition comes in and cuts your business 30%. At that time, ten years into the loan , you still have an outstanding loan balance of 120K and your autos are worn out. So, you call up a local distributor and get a quote for one new auto for 150K or so. The new guy with his shiny equipment is eating your lunch, so you reluctantly agree to the reload. You're back in as much debt as you were on day one, and just struggling to make as much money as you did when you first bought the place. Scenarios happen like this more often than you hear about. The longer the amortization, the greater the risk IMO. Thats why I think longer term loans are a bad idea.
I guess the idela situation is to amortize over longer term with no prepayment penalty, but have the discipline to pay on a short schedule. That way you can scale back if lean times comes.