If you flip on a regular basis (vague term that gives the IRS flexibility to determine if you are materially competing with taxpaying businesses), then UBIT would apply.There is no regular taxation to the IRA, so no income or self-employment tax.  

First, one of the side-effects of owning RE is ability to control and alleviate exposure to taxation (talk to Brandon about that).

Then I'm looking on my states assessments and taxation website to see who purchased the house.

Real estate taxation is a vast topic, and it can take countless hours if you get into podcasts and blogs.

The reason I prefer this have to do with taxation.  

You will learn so much about business, capitalism, taxation, what is wrong with our country, meet many different types of people, your own flaws and strengths and the list goes on!  

Income from leveraged portion of the property will be subject to taxation so be sure to consult with a knowledgeable CPA about tax consequences (this is not the case in a Solo 401k, which is one of the reasons it makes it superior to the IRA). 

There need to be a shift away from the 'for the rich' attitude of taxation to the 'for the good of our country' taxation.Dan Dietz

@Risa Hind I'd like to second what @Ken Badziak has said (and of course I always like a guy that BP's with a glass of wine in hand ;) I would like to point out, however, that in addition to all the taxation issues you have the issue of reserves to consider.

Flipping houses in an IRA, if done on a regular or repeated basis is subject to UBIT taxation, since this is considered a trade or business (and therefore this tax-exempt entity is competing with tax-paying businesses).