I wonder what's the highest difference between the points you pay in the auction to go first, and the score of the first word. In a (still being played) game, I won the auction with a mere 3.5 points, and played “dozened” as the first word, for 156 points, a difference of 152.5.

My gwg_robot's record is in game 119904, where it won the auction for 7.5 and made CEPhaloMETry for 180, a difference of 172.5.

The best initial word it has ever found is spoliated in game 122115, for 198. But its opponent timed out wihtout ever making a bid.

My highest ever score was in game #63229. It was right at the beginning of the game, I placed the word C[onsu]MPTION and earned 180 points. My opponent passed on 0.5 which meant I had a 179.5 lead.

I found a higher difference than the ones already mentioned.

In Game #15957, Dan Thomas bid 18.5 points for the right to go first. He found EXERTIONS for 216 points, giving him a lead after the first move of 197.5.