Hi Blake,
I didn't mean to suggest rental properties, but your post said you were focusing on them, and multi-family properties, by the best use theorem, are the best for cash flowing as rentals (unless you own a hotel or commercial property, etc..)
As far as how to fund the deal with a partner, that will be up to you. I simply put the idea out there so if you were thinking "how can I get the funds required for the next deal" you aren't stuck. You can also consider hard-money lending, but that is more of a short-term loan option, like for a flip or possibly BRRRR if you can get a bank to refi you out with no seasoning period.
As far as buying a home that you can do AirBnB from, it is certainly a creative strategy. Consider the "opportunity cost" of your investment, or the cost of investing in this home, vs. say a duplex of a similar price (which isn't fair b/c duplexes might cost more for a comparable quality). At any rate, if cash flow is the main goal, it makes sense to put your money where you get the most cash-flow. I don't know what the answer to that question is in your area. Quite often, the numbers on a quad, are better than a triplex, are better than a duplex, are better than renting a SFR. Though I don't include the AirBnB profits in that ordering. As a quick aside, moving the laundry is no big deal (relatively speaking, it will cost a few hundred dollars, maybe up to a few thousand)
Also consider that the AirBnB lifestyle will become a full-time part of your existence, especially considering you are living on site. Living with your tenants is not for everyone, short-term or otherwise.
Looking primarily at the AirBnB part, my question is what in the area makes your basement an attractive option for domicile? Are you near a big city center or tourist attraction? Do you see many other rentals in the area, signifying some kind of demand? You have the supply but making sure demand is healthy is always the other half of a business proposition.
Sounds like your head is in the right place. Don't forget to talk to an accountant about the tax ramifications of your moves.
My 2 unlicensed cents :)
Good luck!