How did you handle unexpected service charges and vendor tip creep once you got past your initial venue minimums?

How did you handle unexpected service charges and vendor tip creep once you got past your initial venue minimums? Update from me — I called the venue and asked for a line-item breakdown, and it turned out half the "surprise" was a 22% service charge that does NOT include gratuity, which nobody explained upfront.

What actually helped:

• I asked every vendor in writing: "Is gratuity included in this quote, and is the service charge the same thing as a tip?" Two said yes, tip included. Saved us $600.
• We pushed back on the cake-cutting fee by having our caterer do it — free.
• I built a 10% "fee buffer" into our budget spreadsheet after this. The estimator on this site has a contingency line for exactly this reason.

Lesson: the quote is never the number. The number is quote × 1.25, roughly.