Either selling on a land contract, or takiing a note can the taxable portion.

My first question is: does this trigger any kind of taxable event?

The use of debt-financing in an IRA generates taxable income to the IRA in the form of Unrelated Debt-Financed Income. 

For my clients, if they have a theoretical question (Will the sale of a rental property generally be taxable?)

If your IRA were to borrow $10,000 to purchase the $15,000 note, your indebtedness would be 67% and your taxable income would be under the $1,000 threshold for filing 990-T, assuming you don't have other taxable income from other properties/activities. 

If the property is ever retitled, even from the LLC to personal name, this will trigger a taxable event. 

It still would not result in a favorable tax situation for you, but it's a great way for the parents to reduce their taxable estate in a tax free manner.

Then you deduct your expenses and come up with a taxable amount.

For example, for 2008, if you were married, filing jointly and had a TAXABLE INCOME of $100,000, you would actually pay $17,688 or 17.68% of your income in Federal Income Tax (as opposed to 25%), even though you were at the 25% marginal rate.Next, you would need to consider the depreciation of the rental property, which will significantly lower (or erase) the taxable income from the rental property depending on your individual circumstances.

I'm thinking that since the LLC and myself owned the corporation anyways it would not be considered a taxable event.