For you prospective Buyers, the best way to describe the Deduction and over-all process is as follows;

The Builder will complete the refurbishment of the Historic Façade to as close as possible to its original condition. The project is in a Historic District, and the building will be nominated for Historic Status (which it presently lacks). The Builder will negotiate the Acceptance of a Permanent Façade Easement for the preservation of all historic elements of the exterior of the structure with the San Antonio Historic Conservancy (which has already indicated its willingness to accept). 

They will not have ownership, but will have approval power on any material changes (outside of normal maintenance) of the Façade after their formal acceptance of the Easement. In return for this dedication, the Builder will be allowed to complete a Federal Façade Easement Tax Appraisal. This Appraisal will be the basis for the Federal Tax Deductions, of which the owners will receive a pro-rata share (according to their Sales Price). A summary of the Tax Deduction Appraisal will be given to each Buyer at Close, and will be included in their Taxes as the basis for the claimed Deductions for the years that they choose to utilize it. The Deductions can be carried forward for up to 16, and across any business profits stated by Buyer. It can be utilized to offset up to 50% of each yearly tax load, until it is fully utilized and expended. A hard copy summary of the parameters of the program will be included in the Purchase and Sales Contract for each buyers review, preferably by their tax preparer.

Essentially, it is a huge boon to the deal, and amounts to a dollar for dollar Incentive for buyers, since they would have had to pay those future taxes without it.