I'm last minute changing my entry - withdrawing Executioner, entering Mason's Lodge:
Mason's Lodge • $5 • Action - Duration
+1 Buy
Until the end of your next turn, cards cost $1 less (to a minimum of $0) for all players, and all players get +1 Buy at the start of their turn.
Whenever a player gains a card after their first, you get +1 Coffers.
(also, to head off the #1 criticism of "why would i buy/play that", you get two turns of +Buy/Cost Reduction to everyone elses one turn of it, your second turn after you have a big ol' pile of coffers from everyone else taking advantage of your group price reduction)
Bridge for everybody is a very cool idea. I first thought that getting some Coffers does not make up for the lack of the -1 Coin token attack (of Bridge Troll, the benchmark) and the powerful gift of a Highway plus a Market Square for the other players but after running through some simple examples, the card looks similar in strength to Bridge Troll. But only in multiplayer:
If Bob and Clementine each buy 3 cards such that Alice gets 4 Coffers, the cost reduction amounts to the equivalent of 3 Coins for each opponent. So relative to Bridge Troll that's a difference of +4 Coins for each opponents (relative to the Bridge Troll benchmark the which implies that the -1 Coin token attack has to be considered) and +4 Coffers for you.
If they buy 2 Cards, it is +3 Coins vs +2 Coffers.
Seems decent for Alice.
In a 2P game it is different though. Here Bob buying 3 Cards is +4 Coins vs. +2 Coffers and him buying 2 Cards is +3 Coins vs. +1 Coffers. That's too good for Bob.
So I'd try out a version that gifts a Coffers on the very first buy but only for one opponent.