Welcome to BP @Anna Gorres!
You mentioned you're into interior design - with your background, have you considered partnering up with investors focused on fix & flips, or maybe even some general contractors? Maybe offer to help on the design side for a small piece of the equity? Seems like a sweet way to get in the game if you can find the right partner!
As for your questions - @Tim Swierczek and @Jordan Moorhead pretty much nailed it,
1) When doing research, I use zillow, hotpads, apartments.com, craigslist, and rentometer.
2) I'd say in general SFH are actually more attractive to tenants because they get more privacy. However, bigger units, 4 or 5 Beds, are always going to be harder than 1-3 beds because it will either have to be a family or a group of friends, and I can say by experience that trying to get 4 or 5 people to agree on a place can take time!
3) You hit on the most significant factors here. I would add prevalence of crime to that list as well, though. Google "trulia crime heat map" then search your neighborhood and you can see the neighborhoods with a lot of crime.
4) Ya, I'd say most people would not consider minneapolis a "landlord friendly" city. There are quite a few inspections involved in the rental process, and all of those take time. However, I'd still advocate buying in the cities because the rents are that much better here! Especially if you go for a small multifamily, 2-4 units.
5) I don't have much input here since I never even really looked into buying a condo. I didn't like the idea of paying HOA fees.