We don't really have a budget. Our income is around $260k per year, family of 4.
Last year, following trips: ~$1400
1. 2 days camping in the desert, 2 days Palm Springs -~$400
2. 2 weeks visiting family on the opposite coast (used miles for tickets, plus train in between) ~$800 (included a last minute stay in a hotel due to flight delays)
3. 1 week visiting national parks in Utah (didn't happen, we got the stomach flu, only made one night in Las Vegas and went home): $170
This year: $4300 +
1. Legoland: $700 (2 nights in a hotel, one day at park, family of 4 + MIL)
2. That Utah trip (we were able to transfer our reservation for a small amount of money) $1200 (mostly Air-BNB, but also gas)
3. Trip back East (my niece is graduating): $2000 (this is an estimate, haven't bought tickets yet)
4. Trip to get my kid (we are leaving him back east for a couple of extra weeks after the graduation): $400
5. Maybe some place over Thanksgiving.
So, I'd say in the last few years, $5k would be a high year. Prior to having kid #2, we would spend more. One year we went to Hawaii ($4k spring break), DC (oh wait, that was on miles), and at least one other place. So maybe $7k.
Traveling with an infant sucks when you have another kid (wasn't so bad when there was only one of them), and it's not much better with a 3 year old. In general, since kid #2, we've been on the "1 flight per year" path. But we are breaking that this year.