I think the highest was $400 or so, may have been closer to $300, dinner at an upscale place in Del Mar, San Diego. Dinner was probably $200 and I think I gave the driver like $80, or $100. First date too. I always wanted to go there with a good date, so it all worked well. $200 at another spot in Rancho Santa Fe & Javier's in La Jolla. $200 is fairly standard.
I spend on food, it's fun for me, esp. if someone else enjoys it too.
No limit, it's whatever feels right, and is financially sound. I invited someone to Eleven Madison Park in NYC, that's at least $750 before wine.