Wanted to take it to +29, but missed it by 1. Work, RL, blah blah blah. Sorry Natasha :(
Started:
A Helm of Durin [9] (+23) $4,275,706
Finished:
A Helm of Durin [9] (+28) $18,025,192
NW difference = 13,749,486
@75% = 10,312,115
amount paid = 6,000,000
amount due = 4,312,115