I think it sounds like he probably understands that each deal will have to be analyzed on its own merits, but was just wondering about broader more high level things people follow (like the 1% rule in LTR) that can tell you right off the bat if a deal is even worth running the numbers on before you spend a bunch of time on it.
The answer I think is it depends on who you ask, buyers or sellers.
Sellers - The 10% Rule
In a vacation rental market where a high percentage of homes are STRs and home values are essentially based on STR revenue (they still appraise as residential homes but the market sets their values based on what works for investors), a home is typically listed for 10x its gross annual revenue.
If you go look in the Smokies or in Destin or markets like that, if a home does $120k gross annual revenue then it will be listed somewhere around $1.2M. Obviously this varies somewhat property to property and yada yada yada, but that's kind of the starting point.
Buyers - The 15% Rule
On the flipside, especially now, most savvy investors look for something a bit better than that. At current interest rates, even with self management it can be hard to cash flow with the 10% rule. And the margins are tight which leaves a ton of risk as travel spending is still at record highs and there are no guarantees that will continue in a straight line upwards.
It still works for large companies that are buying these properties as a long term inflation hedge and for appreciation, but for your typical cash flow STR investor the 10% rule doesn't really get the job done, especially at current interest rates.
So a lot of smaller, savvy investors look at 15% as a good starting point. That is, if the purchase price divided by the gross annual revenue is less than 15%, it's probably not a deal worth looking into. These can be hard to find in established vacation markets, where you might have to accept smaller margins.
Again, these things vary from market to market depending on property taxes, etc. But like the 1% rule in LTR it's kind of a starting point some people use to thin out the list before diving deeper into properties and figuring out the specifics of all of the expenses unique to that property.