But I find from personal experience and from my buyers' Airbnb experience that it's a bit of a hassle trying to get guests to rebook at the new listing.I don't know how strict Joshue Tree is at enforcement, but in Denver and Colorado Springs here, you could probably get away with an STR listing for three months without the license.

I'm going to reiterate what's already been mentioned above, but I'm going to actually give you examples of why it's relevant to you to find a U.S. tax professional.1 - You're going to need to file U.S. taxes once you have property down here, there's federal filings, state filings, and sometimes local filings too2 - Tons of tax treaties between the U.S. and Canada that are easy to miss and can cost you a lot of money (important one with rentals - effectively connected income - if the professional you talk to doesn't know what this is, run away)3 - The amount of days you spend in the U.S. needs to be tracked and if you go over a threshold, all of your worldwide income could be taxable by the U.S.4 - Selling real property means up to 15% of your sales proceeds might not be available to you for years (FIRPTA)5 - Lots of nuance at the state and local levels, which both want to take as much money from you as possibleMain takeaway here is that you should find a U.S. based tax person.

I’m not convinced it makes a real difference unless a person has a unique setting.

This is one of the best personal finance calculators I have seen. https://docs.google.com/spreadsheets/d/1oC4gdK5gXIPjyEFTgo3g...

Just a good person too if you want to bounce any ideas off her. 

I have personally been the guy who hasn't pulled permits and got caught...by far one of the worst experiences of my investing career.

Yes, as I'm doing more research, I'm finding that I would prefer to invest in markets that I know personally, so as not to rely on external variables completely.

Do you have a 501c3 that you operate under (and rent the house from yourself), or do you purchase homes with an LLC or personal name, and run as a regular business? 

Also, you don’t need a business license just to look at properties, but if you buy a bigger property, like a multi-family unit, you might need a certificate of occupancy, depending on the local rules.For business trips, most expenses can be deductible, but if it’s part personal and part business, you can only deduct the business portion.

Maybe the section 8 person can help advise you, but I'm certain they will give a disclaimer with anything they say that you still need to consult your own lawyer or read the rules.