There are ways to invest in other types of securities other than stocks in a Roth, such as using a self directed IRA, but these strategies are more complicated and probably not advised unless you know what you are doing and have a nest egg saved up. 

Note: 1231 gains scenarios can be particularly complicated.

Not only because it's quite complicated, but because it's not enough to read the K-1.

I’m thinking about buying a quadplex in an LLC, operating it for a couple months and selling it to another landlord. (Or maybe an owner occupant buyer).Has anyone bought a (tenant occupied) house in a new LLC and then...

Taxes do get complicated, but that's why we hire professionals to do that work for us.I'm also not sure it's a great idea to have two paid-off rentals.

Not your fault for the confusion here.Do you think there is some complicated quantum mechanics going on that an average brained person cannot understand cost segregation, or do you think people could get confused because the OP doesn’t have any articulation skills?

Don't over complicate it.

this is really just such a complicated issue when it comes down to it.

@Colin Williams owner carry financing in a 1031 exchange gets complicated.

They are a bit more complicated and you will need to make sure your title company is okay with doing it.