It probably does not really "save" on taxes in a tax-deferred structure, but would allow you through the benefits of tax-deferral to mushroom that income to a larger amount over time. 

One rental is also close to a mushroom farm that has a strong smell, but the farm is being relocated.

So I found a mushroom growing in the bathroom, got a work order they came and cleaned it up along with mold in the bathroom window, they cleaned it up.

I keep telling him its a mushroom cloud waiting to happen!

Be sure to buy in areas where your compatriots want to be living, not near the pawn shops that spring up like mushrooms around bases. 

East Chicago's property values have mushroomed in the last few months.

The Mellow Mushroom 🍄 was quite tasty!

My Uncle owns the Mellow Mushroom there in Newport News.

While I feel like Denver will continue to stay high on that list for a little while (the diversity of our economy, the tech money coming in, the potential for mushroom exploration make it a multi-faceted place), I would note that in Denver, the rents have not met the mortgage yet, so it's very hard to get good cap rates or cash flow in Denver- despite the demand. 

Due to the more conservative LTV associated with most non-recourse loans, the BRRRR pathway is a little less aggressive than might be possible with non-IRA funds, but it it still a fantastic way to mushroom growth in your IRA via a smart use of leverage.