From D.C. Zoning Administrator Matthew Le Grant's December 16, 2016 letter:
Originally Posted by DFW HOYA
"[T]he facility will provide approximately 3,000 bleacher seats on the west side of the field and approximately 1,000 - 1,500 lawn seats, which is within the total amount of seating previously approved by the Commission."
Unless I'm mistaken, then, the actual seating will expand from 2,400 to only 3,000, not 4,740. That's $83,333.33 per additional seat. I'll bet even military contractor lawn chairs cost less.