Your definition is correct for "legal non-conforming".The "legal" part of "non-conforming" is dropped when it doesn't apply so most commonly people call these units "non-conforming", "finished", "in-law suite/unit", or "bonus unit".Non-conforming: Any property that doesn't meet current zoning requirements.Legal non-conforming: A non-conforming property that was lawfully established under previous zoning regulations and is allowed to continue its use.Based on his posts @Mario Morales is referring to a non-conforming unit.

The issue I have and would like to hopefully get some advice on is the below:In real estate specific tax strategies - it is my understanding that I would be able to generate significant “losses” through the use of bonus depreciation and other strategies. 

And again, make sure it flows naturally.Keep it natural and cleanYou get bonus points if your templates look like they're not from the 90s.

But I have also opened up new cards for specific properties if there is a nice sign up bonus for a card that I know I will hit during the rehab and furnishing phase.

Bonus would be refacing the cabinets if the pricing makes senseI priced out part of the job with HD, windows were somewhat reasonable at $8500 but I was surprised by the cabinet refacing -- Just short of $20k.

This is particularly effective when paired with bonus depreciation provisions.This method not only helps reduce your tax liability but also enhances cash flow, making it a powerful tool for real estate investors looking to grow their portfolios.3.

There are ways to accelerate depreciation via bonus depreciation and other means. 

It's definitely worth it to rent out the bonus apartments.

A cost segregation study looks at the overall building that you purchased and breaks it down as much as possible.The purpose of this is to increase the depreciation expense.Without a cost segregation study, you are depreciating the property over two items(Building and Land).However, a cost segregation study might identify items such as fencing which might be eligible to be depreciated over 15 years instead of 27.5 years.Depending on the year that the building was placed into service, you might be able to take bonus depreciation on certain items.The follow-up question to ask your CPA is will the cost segregation study help me, and by how much?

Imagine having getting 150,000 points intro bonus for spending 6k in 6 months for Amex or Chase for example.