If they are elderly bake them banana bread or send them fruit.

I've read conflicting information about what triggers you to have to pay self-employment tax on your short-term rentals.There seems to be a consensus that the following does:Airport TransportationProviding cooked mealsOffering ToursCleaning during the guests' stayDecorating the property for a party as a serviceI'm not sure if these would cause me to have to pay self-employment taxes, as I've seen these items on a couple of lists but not most:Providing a coffee stationProviding a welcome basket with food itemsProviding bikes and kayaks for the guests to useDoes anyone know where the line is of what you can and cannot do and provide?

If you want cash flow, do nothing and enjoy the fruits of your labor.

Make sure your agent asks when the time comes.Alternatively, go for the low hanging fruit. 

I have a source of funds to buy a building, but I am also trying to mitigate as much risk as possible and not put all my eggs in one basket if you know what I mean!

And if it's vote harvesting, than as everything goes to hell in a hand basket, they will have more hand-outs for those problems, to harvest yet more votes, and on and on the cycle goes of the ignorant empowering their torturer.  

However, I currently have a job as a waiter, and I know that even if my investments go according to plan, they will not bear enough fruit in the short term for me to quit my job.

Don't put all your eggs in one basket.

Having a small taste of the fruits from your hard work and sacrifice will turn you into a success addict and accomplishing your goals will become your crack. 

Essentially meaning that any time of work you put in, be it in lead generation, submitting offers, etc, you won't see the fruits of those labors until about 90 days out.