Will use as a family vacation house, and rent it out STR or MTR.

I'm thinking of a short term vacation rental (that'll just be about patching up a family property that happens to be in a heavily touristic area) and then in the future...

I have never owned a home before but I’m considering buying a place here, living in it while I’m here, then short term renting it and using it as a vacation property when I move back to Canada. 

This was a property in an area my family loves to vacation in because of family ties to the area.

But to touch on some of your points:-Costs to build are probably some of the highest in the nation, other than maybe Telluride or other vacation destinations. 

A little goes a long way you only need 5-10% down for a New primary, 10% for a Second/Vacation home, and 15% down for an investment home even up to 4 units.The home you are planning on selling if you rent it out you can use the 12 month lease/rental agreement to offset (Wash) the mortgage payment if you take cash out so that you do not get hit on the new purchase against your DTI.

The time depends on lease length and how long they've been living there.I would also recommend reaching out to their caseworker (if they have one) to let them know the lease will not be renewed.Section 8 voucher holders are incentivized to vacate quickly in order to keep their voucher and avoid having to pay full-market rent out of pocket elsewhere.Hope this helps!

Another lost his primary residence plus his vacation rental and will be staying with me for the next month while he sorts out his home.

We just cancelled our family vacation to Asheville.

Conde Nast Traveler recently announced their 'Top 10 Trips everyone in the US should add to their bucket list' and it features some impressive vacation regions and activities:- Hot Air Ballooning, New Mexico- Bluegrass Trail, Virginia- Visiting Point Dume Malibu, California- Horseback Riding, Wyoming- Airboat tour Everglades, Florida- Winter expedition cruise, Alaska- Spiral Jetty, Utah- Camping In Acadia National Park, Maine/Rhode Island/Massachusetts - Trekking the Bayou, Louisiana - Wine country, Willamette Valley & Napa Valley Oregon/California