From Dan's perspective, John does not lose out on anything but Dan save's $500.

I have some perspective  as it was 3 years ago I decided to go self employed and count on no one but me, and investing has only grown compared to the w2 days.

This was a pretty big rehab project and took a few months to complete - however, with a $321,000 purchase price, this house is now worth $485,000 and I was able to recover a majority of the cash I put into the deal as well as go from 5% down payment to 20% equity all while owning a fresh new house!

A friend has kids, and they currently have three dogs, a rabbit, fish, a turtle in the house (not to mention the three ducks and six chickens for fresh eggs... of course, those stay in the back yard). 

Not only that, but the framework and perspective it gives on your business building/investing activities are the best I've read.

I'd like to put the marketing perspective on it. 

With the numbers people throw at me, in my area the TLDR/conclusion is most often that ADUs do not seem to make sense to build purely from a resale value perspective.

I'll offer the perspective of global nomad.  

Jason,  here's the old guy perspective. lots of good advice on here, I'm 62 closer to retirement age, I went the SDIRA route with my accounts,  Buying and holding properties in the IRA ,  building tax deferred income  and purchasing houses inside IRA about every Two years. mine are traditional Ira's , Agreed i don't get to hold the money in my hands but it fully remains dedicated to real estate and keeps me on focus.  

From a personal perspective, we only look at pet-friendly STRs when we travel.