I’ve tried to find the answer to my question online, but can’t find anything with a clear answer.Situation is this.

Lots of resources here or online for HOW to underwrite, handy calculators, rules of thumb, quick formulas, etc.

I know that @Manaia Alalamua has one, Alamo REIA is another one, I have one this week.This forum is great to meet people on line, but there is nothing like ACTUALLY meeting people in person.  

We would never accept a contract where the buyer’s preapproval was only from some online company (rocket mtg being the worst, and a non starter for us).

.- There is document storage as well as online document signing.Hope this helps!

New rentals are NOT coming online in response to the hike, there are just fewer and fewer rentals available.Whatever's coming online is also coming from hands-on operators like us.

Or there might be online retail or other businesses with low startup costs (a good book to read on low cost business ideas is "The $100 Startup" by Chris Guillebeau). 

There are free amortization calculators that you can find online that are free to use. 

@Trae JonesThere are online tools that calculate costs based on area

I took a check one time, because I happened to be at the property and was going to the very bank that the tenant was on their way to for the deposit. 75% of our tenants pay electronically online, and the remaining 25% go to a local bank where we have a tenant access account set up and make their deposit that way.