Accelerated Depreciation, Cross segregation and or MACRS?

[Tony Roddenberry]

I'm fairly new to real estate and have quickly learned that the IRS gives us investors a lot of breaks but it comes at a price. The last few hours have been spent wandering around in a quagmire of IRS Publications that have caused the death of extremely valuable brain cells. (I'm running on a deficit already)

My rentals are all BRRRRs and it seems some of the cost of the (R)ehab fall under the accelerated depreciation category. So far I have not found a list, suitable for those of us that are brain cell deficient, that lays out what can or can't be put into this category. I'm thinking things like the new appliances are in the 5 to 7 year category and the new AC can be straight lined for 15 years?.

Does such a list exist? 

Is there a nuts and bolts article on BP that has applied the KISS (Keep It Simple Stupid) method to the IRS Publications for those of us do not view the IRS Codes as a challenge?    

If so I would really love to see it before I go completely  numb from the neck up.

Thanks for taking the time to read.

Tony Roddenberry