If handy with a sewing machine, make your family's vacation clothes. Eating away from home can be expensive. Travel with packaged snacks purchased from supermarkets along the way. Discontinue newspaper deliveries while away from home. Never travel on credit unless you can pay the bills when due.
Rental cars are costly.
If possible, drive your own car while on vacation. Consider sharing vacation homes. Get details from library. National parks, forest service campgrounds, etc., let you camp free or for just a small fee a night. Plan in advance.