Continue renting and investing until you have more income than you know what to do with or have any use for then buy a home.
If your priorities are to invest for income to replace a 9 to 5 personal home ownership should be way down your list of priorities. It is a liability that will cost way to much and drain your ability to save for investing. You definatly do not want to tie up all your cash in a home. It's a life style decision only.
To put it simply the goal of house hacking a duplex is to have the renter pay the mortgage for the entire duplex. Some markets this is possible other markets it might be harder to achieve. This allows you to save what you would've spent on your mortgage payment and eventually put that into another rental property. Then it snowballs from there. Thats the simple answer mind you.
If you are wanting a SFR for your main residence then you either need to make sure that the rent you get, from the unit you use to live in, covers your new mortgage in order to keep the same cash flow and savings. Otherwise you've just incurred more expenses and lowered your ability to save.
I'm not going to directly answer your questions, but I do think there are some considerations going into a house-hack that you have to think about-
The main one for you--do you know you definitely want to live in that property that far down the road?
I'd say for you too, weigh the numbers. See what the numbers would be on this house-hack versus if you just lived wherever you wanted and bought straight investment properties.
When buying a primary residence, I alway ensure it is in an excellent location with the potential for appreciation. I also ensure that the rent (after I move) will cover at least the PITI. When I'm in a SFR, I house hack by renting out the additional rooms (albeit I'm single). When I'm in the MFR, I house hack by renting out the other apartments and still rent out my rooms. I try to do this once a year :). Since I ensure that the rent will cover my mortgage, I'm comfortable with buying "nicer" places with this strategy. I focus on things like the 70% or 1% on my traditional rentals. It's a way for me to diversify into Class A, B, and C properties. Cheers!
My wife and I have a guest house at the front of our primary residence that we rent out as a short term rental on AirBnB. Very easy to do and it pays our entire mortgage plus a little more.