I would really like to have a vacation home in California or AZ that my family can use to get out of the city and be closer to nature.

@Sam Liu You can be under contract for the replacement but naturally your relinquished property has to close before you can take title of the replacement. 

In that case it would effect the nature of your write off and the deprecation schedule of course

Cultivate relationships where referrals become a natural part of your interactions.

Can you please elaborate why the business activity nature of STR will be treated differently due to part of the property being primary residence and under which rules?

From a management position, Evan is correct in that most issues are dealt with on a business hours timeframe vs. 24-7 for anything residential in nature.

If not in the city, and not in the ETJ, then it's a lot easier, provided you can get water (probably need to drill water wells so thats a separate ground water district) and sanitation (some sort of onsite sewage treatment).

I don't know the CO law.A duplex by nature is multi-family.

Of course as nature of things the community of investors in my area that are investing in the US is small and no united network of investors exists.Couple of days back a large conference of investors took place and I mingled with everybody and handed out business cards and managed to assemble 20+- investors to open a REIA. 

You have to adapt to the new era of higher cost of capital, lower supply, population changes, natural disasters, etc.