I started using Mashvisor and AirDNA this week while trying to evaluate listed homes for short-term rentals. What I've found:
AirDNA has good info for the most part, but as was mentioned, they can't separate between "booked" and "blocked." One of the houses I'm looking at buying was listed as 42% occupied with a $242 average nightly rate, but revenue for the past year was only $8400. Makes no sense...
Another downside is AirDNA shows my studio apartment revenue fairly accurately for the past year, but my larger condo's revenue seems to be the sum of both properties, because I haven't made anywhere near their numbers on that unit with only Airbnb. So when you're looking at a listing's revenue, be aware it may be influenced by the host's other listings.
I actually spoke on the phone with a MV account exec today to get explanations of why two houses I am looking at weren't on their site, and why there is no Airbnb data for the city I'm looking at, Wilmington, NC. He basically said it's still in beta testing, so there are bugs, but also, if a property is only on 1-2 of their MLS sources, but not the others, they may not list it on the platform b/c they want investors to have info from multiple sources, not just Redfin or RentJungle, etc. I would think any info would be useful, but they seem to think that investors are planning to use their site exclusively for decision-making, and they don't want to open themselves up to lawsuits because someone's property is performing the way the platform indicated.
I think MV has much more potential to as a more useful tool if they get all the kinks worked out, but for now, AirDNA is providing the most accurate info for me.