While the DSCR calculation as noted above is a bit "aggressive" and looser by not taking into account many expenses, its somewhat balanced in that these are 30-year typically fixed rate loans where the rents should increase much more over the term than expenses (and largest typical cost - debt service - is locked in). 

If you're more conservative, you might want to increase your fixed income allocation.Income needs: If you plan to live off your investments in retirement, ensure your portfolio generates sufficient income to cover your expenses.Remember, this is a general guideline.

I'm sending around 8k in postcards and my printhouse just increased their prices by 30%

Very simply, multifamily spreads out your risk if a tenant moves out generates more income with more units and disproportionate amount of increase in expenses as there are more tenants to deal with.

For instance, when new industrial parks or company offices open up, it means more people looking for places to live, potentially increasing your rental income.

Do you find being pet friendly increases your occupancy OR deters guests away who don't want to deal with past pets?

It's essentially financing a portion of the transaction by increasing the purchase price by the contribution amount. 

Yeah, okay, while you at the same time increase your booking fees. 

The first thing we noticed overnight was the platform's speed, which increased drastically, as well as the new customer support who were checking on us consistently (which was a new thing), so things were turning out for the best, and we were making 1-2 deals a month out of that. 6 months ago, 10 DLC was getting approved in 3-5 days instead of +10, and we upgraded to the managed plans, and had a person manage our accounts, and were able to get to 3-5 deals.

If you're aiming for appreciation, look for a market with growth potential and increasing property values.