I think if you understand the price per unit as well as the price per square foot in the zip code and nearby zip codes that will give you a good idea of the comparable market analysis approach and appraiser might use.

Be sure to review property tax statements and verify any zoning or code compliance documentation.

Example: I define what zip codes (or neighborhoods) that I buy in.

We live in a very intersting, diverse, and complicated market and understanding the intricacies is very important - especially for a new investor.Markets in the same zip code even have their own submarket and tendancies depending on location and its important to look at things hyperlocally in philly.

But that doesn't seem like a good idea to me and would probably not be to code. 

You need his rank, time in service (you can even guess really, doesn’t vary a ton), and zip code.

Just for your own sake I would pick just a few zip codes to focus in on first and committ to reviewing/analyzing 50-75 properties on those zip codes.

I may be wrong in my understanding of the real estate code of ethics outlined in the Arizona state statutes, and everything else I've read regarding real estate transactions, but as far as I understand it the original agreement to sell is null and void due to the nondiscolure committed by the real estate agent/broker first in the fact that he signed the agreement to sell as the buyer, misrepresentating himself as the agent and stating he had a buyer/investor and Secondly because the agent involved should not sign in representation of the buyer but may only accompany the buyer to the signing (it was done through docusign, I signed first and then was notified that the buyer had signed and downloaded a copy, I didn't look at who the buyer was until just last night).

Awe, a handbook should be the simple version of rental law, imagine what the code reads like.  74 pages of insanity.

For the modifications, cities generally focus on safety and code compliance, but since you're considering structural changes like wall removal and garage conversions, obtaining permits is key.