You should be exempt so long as you follow the guidance under Rule 3(a)(4)-1 under the Securities Exchange Act of 1934.

The local rules constantly change.

I've never heard of such a rule but I'm wondering if some of the more seasoned investors have.

No, you cannot, there're very specific rules against it, despite the YouTube webinars encouraging you to deduct them (the symphony players lost a court case against the IRS trying to deduct their performance tuxedos)and so on.I know it's tempting to think you're sticking it to the IRS, but in the end they will stick it to you.

As we buy more directly from homeowners, I don't want to deal with all the disclosure and compliance rules that realtors have. 

@Davina KraegerA 1031 exchange is a great way to defer tax to another day and ultimately skip paying it all together.There are many rules involving 1031 exchanges - however the 2 main dates to remember are 45 and 180You must identify the property that you will purchase within 45 daysYou must close on the property within 180 daysThe sale must be done with the use of a 1031 intermediary.

It doesn't look like there is a "rule of the thumb" for this for a variety of reasons and that is totally understood.However, would using the CPI from the last 12 months make any sense?  

So I know there are pretty strict rules in place to keep your personal dealings and 401k dealings separated. 

I am less positive about how well blockchain is going to change the rules of the game.

Then when shopping remember HOA's have their own rules.