I've just recently learned of a very important avenue of passive income that those with funds enough to invest in real estate should heavily consider. Rental properties are a common thing and you hear about them all the time, but something that is less frequently talked about (although it is known in some circles, I hadn't heard of it until recently) is the purposeful investment in real estate in locations where people are commonly vacationing and using Airbnb. My girlfriend's parents are in town and are staying at this beautiful condo in a renovated Mill Building which has become a set of Condominiums (absolutely beautiful) and they explained to me that they are doing Airbnb and saving tons of money compared to a Hotel. The place is 10x as nice as a hotel too. It is a great way to get supplemental passive income and have your property pay for itself if you are in an attractive place for an Airbnb.
Doing this allows you to charge people on a nightly rate, similar to a hotel, which is a higher rate than what it would be if you were to rent the apartment/condo/house out. The fact that they are paying a higher rate (even though it is far less than a hotel), means that even just a week or so worth of customers a month will pay your mortgage and any other people staying will give you passive income. That being said, in order to use this investment vehicle, you must be able to have an additional property that you use just for renting out, so it isn't for minnows, of course (like myself haha). However, I plan to carry out an investment like this in the future when I'm in a position where it is actually feasible!