On my breakdown for newbies, my aim was to give a small example of the various parties ( on contract only) during a wholesale r.e. transaction which depending on the location(State) of the subject property and the position said party is in can lead to discrepancies, especially if one is the wholesaler. 

Along with the comments in this forum, I do believe that if you are dealing with FSBO and are marketing to this segment, having the ability to get comps would be beneficial.I would def check the property tax value, and also do a quick search of any existing properties for sale - I will then see if there is a big discrepancy between the asking price and the property tax value.

Small, but consistent, discrepancies will create a compounding interest affect that make housing unaffordable because it will force housing to occupy an unreasonably large portion of consumer spending with time.

In other parts of the country and with high rent values, there is certainly some major discrepancies in the rule.

You have to gather info through multiple sites (at least a dozen) to arrive @ a median price per property when trying to do CMA's (if you don't have access to MLS).Even with your info Bryce (which we thank you for) we still see a slight discrepancy at what is listed @ $295K vs. what the wholesaler is offering @ $285K...

I’ve seen huge discrepancies in taxes over many cities around the country and places in Europe as well.

Proforma RET (this seems to be the biggest discrepency, and I live in a high RET area) is based on what the seller is paying, based on their purchase price. 

That most likely would have acknowledged the discrepancy. 

Do you have a $139k discrepancy on your income stream and you already signed the contract?  

There could be many reasons for the discrepancy.