STR can be a great way to start investing. It's how I got in to and it changed my life from day one. I thought you asked some great questions, so I listed them below with my answers. I hope it's helpful!
Does anyone prefer Airbnb over Vrbo or vice versa?
It's market dependent, and it also depends on the type of guest your property will attract. In general I prefer Airbnb. I generally recommend trying both, at least at first.
Do you guys think the market for short term vacation properties will ever go out of style in the sense of laws being created against them (being phased out sorta)?
Again, very market dependent. Will it go out of style? No, probably not. As far as the legality of it, that is something you'll need to learn and know in detail for your market. If your municipalities haven't landed on legal parameters yet, then it's something you'll need to pay close attention to, and always have a few backup plans if the laws change and you can't operate as a STR anymore.
How much do you think a first time young person who has never bought a home would need to save for a decent property return investment?
If you're buying a home to live in and renting out the rooms, you only need enough for 3.5-5% down plus money to furnish. If you buy as an investment property (not living there) you'll need 25% down plus furnishings. Of course the cost of furnishings could vary dramatically, as I'm sure you know being an interior designer. I had a friend (also a designer) furnish her entire vacation rental for a couple thousand dollars, buying everything at thrift stores. The place had a cool, vintage vibe.
If you really want to get your feet wet right away, without risking a bunch of your own cash, then you may want to try airbnb arbitrage. Essentially you rent a home or apartment, furnish it, and sublet on airbnb. You'll need to be 100% transparent with the owner and probably either pay him higher rent or cut him in on the profits. This is how I got in to the business, starting with only a $1000 deposit and started netting a LOT of money from day one. After 2 years we had enough to put 25% down on our next property. I'm happy to discuss airbnb arbitrage further, or you can search the forums here and find many others doing it successfully, even at large scale. I personally prefer to use it as a starting point with the goal to eventually own the properties
Can I use an FHA Loan for one of these properties?
If you're living it it, yes. It''s called House Hacking and it's one of the most effective ways to get started in real estate investing. Either rent out the rooms individually, buy a duplex, triplex, or fourplex, or a house with a mother-in-law. There are many ways to do this. Just yesterday I saw a gorgeous $1.1m lakefront home for sale in my market (extremely expensive market) that had two airbnb cottages in addition to the main home. Since the cottages combined would bring in around $7k/mo you could essentially live for free on day one.
Do you think it’s smart to mix my portfolio with short term vacation rentals as well as more stable long term rentals?
It all depends on your goals. Personally, I do have some LTR's because I wanted to balance out the risk a bit. However, I should probably convert them to STR and I'd make a lot more money. I've been doing this for several years now and feel pretty confident I can continue with no problems, even if the demand slows down.
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I hope those answers were helpful. I'll also add:
The incredible thing about vacation rentals is creativity gets rewarded. I am a designer as well (furniture designer) and I always look at the vacation rental as an opportunity to design an incredible experience for the guest. Of course you want to make the place beautiful and comfortable, but when you start thinking "how can I make the guests experience exceptional and memorable" then you start considering every little detail. Currently my partner and I focus on cabins, and our prices are 300% higher than every other vacation rental in our area, and we're 100% booked with a waiting list (it was this way before Covid). So, more than any other area in real estate, thoughtful design has the opportunity to unlock exponential financial reward.