Always establish price ahead of time.
Good advice but the ship has sailed. Now... personally I have never done this type of work, but I my own ruminating I thought $10 per block to be a fair price for this type of work. After all, it's time, talent, batting, and scraps. That said - it's a almost $4000 project by that metric....steep for a memory quilt. Perhaps $$2000? Still steep, but perhaps other quilters who do commissions of this nature can chime in with an educated voice. I think a lot but actually know diddly -squat.