Advertising, marketing, and mileage add up but realistically the only thing you need to do is spend gobs of time belly-to-belly talking to people, handing out your card one at a time as fast as you can, and listening for opportunities to help people.

They could be good source for leads, they should be able to do the site work or refer to someone 'recommended' who can.For bare land- Your short 2month timeframe for permitting (city or county) and utilities is not going to be realistic or even close, most of the time.Your best bet is to find land that has a mobile (demo and scrap it) then replace.

35-40% is a more standard realistic operating cost. 50% is too high.

This is why $400k for a 2 bedroom on a mountain in Sevier County is realistic.

What’s a realistic IRR to expect on a long term rental in the current market?

So, it's likely to be seen by some fans of Wright's work.Is that $2m a realistic estimate for something like this, or is that just wishful thinking?

That is not realistic here whatsoever.  

To make things more realistic, multiply the weekly rate by 104 and see if that is greater than the purchase price.

It's imperative to learn the numbers to get a realistic idea of cash-flow vs. selling. 

If this isn't interesting enough, posit your own variables but try and keep them realistic.