The final phase is to exit via UPREIT for OP units rather than cash, with the REIT getting a step up in basis that can be depreciated again, while still not triggering any capital gains for you until you convert
They're only deferring the tax on $70-80K, correct?
Yes, if they sell normally. But usually capital gains tax is lower than that on the income so overall they're saving.
To be explicit: They use the $70-80K depreciation to offset their rental income (which often means they pay no tax on the income for that year and several years after). They'll pay it eventually when they sell, but at a (usually) lower tax rate.
There are tricks like 1031 exchange to avoid paying taxes when they sell, but I don't know how depreciation benefits factor in to those.
First, depreciation on real property is about 27 years. 80k annual depreciation indicates a 2.2m purchase price.
Corporate capital gains don't get a special rate. They're taxed the same as regular corporate income. The 1031 like kind exchange is also very difficult to achieve as the bar is very high even under the Trump admin.
That's straight line depreciation. Look elsewhere in the thread and you'll see cost segregation and bonus depreciation. To give you an idea, I once invested $50K in a multifamily property and my depreciation for the first year was $18K. I never paid taxes on any of my income (but did pay more taxes when it was sold due to the lowered cost basis).