Obviously if you start buying 3, 4 or 5 "second homes" then underwriter's are going to start looking into this with a fine tooth comb and most likely find out if you have a history of getting rental income from these properties.That being said, I am helping a client get his 3rd "second home" right now in Arkansas.

I have had three past mortgages and every one went through my bank statements with a fine tooth comb to figure out where my down payment money came from. 

Deff looking to comb through it.

They can go inside of house and inspect everything with a fine tooth comb,they can’t go inside homeowners home.

My internal checklist has me combing the exterior for roof/gutter/siding damage, check the garage, inside check all flooring/ceilings/walls, how the house is heated, age of furnace/HWH, age/wear of appliances/showers/toilets, basement check for cracking walls/signs of water, attic - mold.What's this rookie missing?

Just desperately combing through markets to find any decent prices!

I comb the MLS every day or couple of days.

Go over everything with a fine-tooth comb to increase chances of +ve cashflow

To clarify for all Brent Combs is not an employee of, associated with or in any way related to Holton-Wise.

Also comb through AirBnB's amenities list and anything that you can cheaply get and add to your STR, do.