If I offer a complimentary stay in my short term rental to friends, property managed by management company, do they still have to pay taxes and fees, besides cleaning fee? 

They are complimentary and directional.

We provide our tenants with X number of "free rides" at the beginning of the school year, but they can use the card beyond those complimentary cab fares.  

I'm launching a stylish high-end STR in California wine country and I was thinking about contacting some travel influencers for a complimentary stay at the property in exchange for posting about their experience to their followers. 

As a courtesy, and somewhat of an apology, if you previously reached out to me and I have not contacted you back, I will give you a 30 minute consultation (which I normally charge $100) as a complimentary service.

Then once you have diversified in the markets you know you can start by adding complimentary markets to lower your seasonal revenue standard deviation. ie if you own a summer market and add a winter ski market you can begin cutting your standard deviation in income by 40 - 50% offering a lower risk profile on the portfolio. 

Hotels give complimentary breakfasts and leave chocolates, etc.

Placing one tax-shelter (an annuity) into another tax-shelter (an IRA, that is what most likely you have right now) was not the best choice for you.Feel free to contact my office and request complimentary 15-minute consultation, send me copy of your statement ahead of time and I'll be glad to help you figure out what it is that you have.

If you have another (complimentary) avenue to make 'deals,' then it would make sense (like potentially networking with: RE agents, mortgage lenders, title cos, etc.) that they might well be receptive to either reselling 'flips' to you (?)

@Gary F.Study for real estate license as well through this online school: https://www.alliedschools.com/real-estate-programs...It comes with a complimentary DVD also..