My personal taxes involve fairly complicated investments that also require multi state filings.  

That plays a role.3) Where this gets complicated is you are doing commercial financing.

@Jason Malabute Yes, it is easy and straightforward, UNLESS you have a complicated structure in your LLC.

@Gary StarkReal estate tax return preparation is very complicated.

Making matters more complicated, these Sec. 1031 tax basis calculations are needed before a cost segregation study can be recommended.

It's not super complicated, but you can pull out cash to rehab the deal and then put it on the market with no prepayment penalty. 

This means thousands of dollars more in engineering, surveyor, and architectural cost plus months of extra work.Original 2-story garageHISTORIC CONSIDERATIONSTo complicate things further, the structure is located within a historic district.

This is very complicated.

Tax techniques include depreciation, mortgage interest, costs, cost segregation, and tax-deferred growth.

Tenant laws making it much more complicated to be a property owner in Multnomah county.