I am not much help when it comes to vacation rentals but I have heard HomeAway.com is a popular site for advertising vacation rentals.

Think of one hit wonder "song writers" versus success and popularity through out but no "wonders".

@Julian BuickNo idea, what you're likely to get with later writings is tid bits of the wind blowing in regulations, particular outlooks, for example; they may mention the popularity of wholesaling and address issues or they may mention Dodd-Frank or Consumer matters with those in foreclosure.

She told me recently that, thanks to the growing popularity of the HGTV reno shows, renters are asking for more of the 'trendy' things showing up in the TV shows rather than being content with the same bland styles they've liked for the past 10 years.

These were popular for decades, no more, there are no advantages and still more  disadvantages, like insurance coverage, loss payee collections, authority of a buyer to conduct official business, like building permits. 

Rent to own was popular for MH in the past not so sure now with DF.

In New England, you will see tons of them, they are very popular. 

It must be popular.

The topic of Solo 401k/IRA is quite popular here, so perhaps you can do a quick search to see others' experience with this.To answer your questions:1.

This was a very popular solution years ago, but has become much more risky since 2008.