Or if commercial is overbuilt and Amazon is flexing it's muscle then sell commercial and buy residential. 

But I hear there are benefits (tax & ...)to keeping some parts to declare it as a remodel to city/state. 

I would certainly take advantage of declaring 2 different properties (or the 200% rule) in your first 45 days incase it doesn't work out. 

You will have to declare that amount on your current year tax return and pay ordinary income tax on it.

The Service is aggressive when it comes to the practice of basis swapping and the fact that the parent wants to sell at a discount and declare tax will need to handled delicately by their CPA. 

In my case, I grew up in a poor area of the country (declared to be an economic disaster zone by the Johnson Administration in the 1960s [today, it's part of the Rust Belt]).

A 3-day cancellation notice, informing you of your right to cancel your contract if you signed the agreement in your home, or at a place other than at the contractor's office or business;All warranties on the owner's rights; A statement warning, in ten point bold type or larger, directly above the space provided for the signature, the following: DO NOT SIGN THIS CONTRACT IF THERE ARE ANY BLANK SPACES.Whether any lien or security interest is on the residence as a consequence of the contract.An enumeration of such other matters upon which the owner and contractor may lawfully agree.Any other provisions otherwise required by the applicable laws of the Commonwealth.A clause informing the owner about: any and all necessary construction-related permitsthat the contractor must obtain such permits.that owners who secure their own building permits or deal with unregistered contractors will not be eligible to access the Guaranty Fund.Acceleration of payment: No contract can contain an acceleration clause that would require any part or all of the balance not yet due to be declared due and payable because the contractor deems himself to be insecure.

Or are you just mad that someone is standing up and declaring a very common problem among people in your profession?

As part of the building permit application process for a secondary dwelling, the owner of record shall submit a declaration, under penalty of perjury, stating that the secondary dwelling is not intended for sale separate from the primary residence, but may be rented.

Not being an agent, it does not affect me but I would say when you put in your LOI, declare that you are an agent representing yourself and your commission expectations.