Make sure you do your math correctly when analyzing property taxes…they will be eye opening.

It depends. all you talked about was the property but financing is more about the borrower, their experience, their credit, the cash available etc.

Will the property taxes skyrocket?

The Heloc can also pose as a debt obstacle since its an open end mortgage a.k.a credit card.a mortgage is also set up over 30 years so it offers a lower rate and payment. 

The rise in home equity over the years can be credited to two key factors:1.

Get knowledge, follow experienced people, and leverage wisely.My Take:If you have two houses, excellent credit, and motivation to build wealth, you can learn to manage your money responsibly.Use HELOC, credit cards, and business credit funding to leverage your cash and buy properties faster.

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

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.

No management costs as it would be self managed, and estimated property taxes by the average of the past few years.

Low barrier to entry, low taxes, landlord friendly, and areas that appreciate + cash flow.