After the new home is built, I plan to sell our primary house.

to your point, if you save up so that you're in a strong financial position, house hack a solid duplex in a decent neighborhood, make smart decisions, and hold it indefinitely, you'll be fine.conversely, if you have $0 and somehow start out with a risky flip, or borrow $20K and spend it all on a magic mentoring program, or buy a terrible property in a neighborhood you've never been to, you may not be fine.

Another option I’d recommend considering is leveraging business funding, which can give you the flexibility to scale and take on multiple deals at once without depleting your personal savings or credit.For example, you could access $100K to $150K in 0% interest business credit—this doesn’t report to your personal credit, so it keeps your debt-to-income ratio low.

I've included an example below to help illustrate this.So different lenders have different rates (which do vary even for DSCR loans) but these are factors they all consider.See example below:DSCR < 1Principal + Interest = $1,700Taxes = $350, Insurance = $100, Association Dues = $50Total PITIA = $2200Rent = $2000DSCR = Rent/PITIA = 2000/2200 = 0.91Since the DSCR is 0.91, we know the expenses are greater than the income of the property.DSCR >1Principal + Interest = $1,500Taxes = $250, Insurance = $100, Association Dues = $25Total PITIA = $1875 Rent = $2300DSCR = Rent/PITIA = 2300/1875 = 1.23If a purchase, you also generally need reserves / savings to show you have 3-6 month payments of PITIA (principal / interest (mortgage payment), property taxes and insurance and HOA (if applicable).

Dave Van Horn is a collegue of mine and I am glad that he was able to point you in a direction that helped you feel better about your retirement planning. 

Years ago, being a property manager was what I planned on doing for my retirement gig.

We have some of those calculators we plan to to add in 2025 for those who want it all-in-one.

With some proper planning and the funds to lock in materials early, you can have an efficient build, but certainly not fast.

You should have a ton of demand for co-living in that area, particularly if you're on a busline.If you plan to sell anytime in the near future - I'd advise against putting a tenant in there well under market on a long term lease.

If you think the money will come you quick in anything you do you’re better off just dreaming about what you want and saving your money and work for someone else to make their dream come true.