Another thing to keep in mind, is that if you choose your markets wisely, your rental income will grow over time.

Size-wise, it's about like combining Rhode Island and Connecticut and then some.

Tax wise, you'd most likely be forming a partnership if your parents contribute equity (unless they are just gifting you some money). 

It may be wise to have a way to justify it to the tenants but bottom line is that circumstances change. 

I tend to buy in the Southern half of the US for 3 reasons:1) you get much higher year-round occupancy rates in the South & it’s simply tough to earn a good ROI in the North if your place sits vacant for a big chunk of the year2) Culturally, the Southern half of the US seems to be a lot more accepting of STRs regulation-wise.

I could build a duplex or fourplex, which may be a smart idea cashflow-wise, but might hurt the resale value.

IMHO you are wise to look into Multi-Family.  

Yes, but those who go in with the mindset of learning the industry and how to invest wisely make far less mistakes and make more money in the long run. 

As for selling multifamily, I'm more concerned that with the price of houses in the area, buying multifamily wouldn't make sense numbers-wise for an investor.

That's a decent rise in a mere eight years.Unemployment-wise, I know Kansas City is around 5% and St.