If you have an ownership LLC and a management LLC, you will start having a lot of different signature blocks that all need to be kept straight.  

For illustration purposes if there's a block of identical homes of the same vintage and one was just renovated and you intend on renovating the same vintage home to the same specs (and was of same pre-renovation condition), you can make reasonable assumptions.

He could have bought several more on the same block for $6k.

If you do Philly, you have to know the blocks, every block, because the change from block to block is drastic.

Does this jurisdiction require a block foundation?

However, when attempting to list the ADU for lease, the property is currently blocked on Zillow.

Excited to share that I just closed on a newly remodeled Triplex as my first home purchase and 2 blocks from the beach!

If you do be prepared to have a rate of 9.50% or higher which in most cases would be a higher payment than if you simply refinanced and lost the 2% rate.You may also have road blocks with a HELOC that a cash out refinance would not have due to cash in hand and one loan. 

I left the house to drive around the block to give him time, I noticed him standing in the dark, staring out of his window recording with his phone.

You'd prob. get better information on their own from Neighborhood Scout. no argument from me Agents have to start somewhere and not all agents are seasoned pros or grew up in the hood they are selling.. and for sure with low end rentals in the rust belt and mid west it can be very very block to block and you just dont want to take a listing agents word for it.. you know they may have to make their car payment ..