There are currently 33,717 Active Members... If you buy all, i would estimate it to be $65k-$70k if each members was getting 2$ each... thats a lot of money which I would think nobody cannot afford..
Pay Shawn to edit the forum theme and replace the avatar section for your image ? No one would ever be able to cheat you.... Btw mine is available for $6 a month for atleast 2 months .
I think the best way to go would be to buy DP and then change all the avatars to yours. If you tried to buy all the avatars and could get a hold of every single member, assuming it took 1 minute to buy each avatar and you worked at it 8 hours a day it would take you 6 months to get them all by which time there would be a heck of a lot of new member. Yup, the only way to get them all would be to buy DP so the answer to your question is the same as what price is Shawn willing to sell the forum for.
I doubt someone would have that much money..... Btw 1 trillion dollars would have 12 zeros while a billion has 9 and a million has 6. 9+6 = 15 so that'll make 1000 trillion or a quadrillion.