Once you have that cushion, I would than put about 10%-15% aside regularly, split between a retirement fund and non-retirement fund, such as a mutual fund or a stock fund.After your have accomplished that, than start looking at investing in a business or in real estate.

I make great money with my regular job. 

Please do yourself and your family a favor by investing in supply constraint markets such as the Bay Area.

Compare this to places like SF or NYC where few places to expand to and old style rental regulations constrains housing supply to a certain number of units a year so you either buy the higher prices or move. 

There is a housing crisis and the city is getting dense, low supply high demand.

Personally, I pay for the best wifi, all the utilities and regular professional cleaning. 

Less expense as well as you're not supplying consumables, paying cleaning, paying for broken furniture glasses, etc. - Rental policy is required.

For me, it added an extra level of security/ protection above the regular homeowners policy (injury, property damage etc). 

That being said, and despite it not counting against my DTI, an additional payment each month (to repay the 401k loan) pulls more available money from our regular income.

We got the $80k to purchase house from HELOC on first investment property, rehab money was from interest free HD and Lowes CC for supplies and personal savings and business savings from other rentals to cover cash needed.