Super confused on 30-year mortgages . . . ?

[Kyle Shepherd]

Hey folks - I am a noob, and I am confused. I have not done my first deal, but I am always looking at properties and crunching numbers. (I have not done my first deal yet because I am behind the game when it comes to a credit score/history - discussion for another day.) Somewhere along the way since I heard about BiggerPockets several months ago and begin reading/listening to BP stuff, I picked up the habit of using 30 years when calculating mortgages on properties. New SFR on the market? Crank out the amortization-calc.com and find out what the monthly payment would be over 30 years.

However, it would appear that this is wrong - it would seem, based on my conversations with banks and mortgage companies, that I can't purchase an investment property with a 30-year fixed rate mortgage. This keeps coming back to bite me - I am looking at a piece of property that would make a great trailer park, and another piece adjacent to it that already has several on it, but I keep forgetting that the monthly payment is WAY higher than I initially think due to my habit of using 30 years at first.

So 2 questions -

1.) Why do Brandon and friends use 30 years in their mortgage/BRRRR refinance calculation examples and books if you can't do a 30-year mortgage on an investment property?

2.) How would I secure a rental property (SFR) in such a way that I COULD take advantage of a 30-year fixed rate mortgage?

Thanks folks!