- Use your insurance, you could save up to 30$/day
- Hertz is usually more expensive, go with dollar or thrifty
- Some sites like trivago offer specials, try them all expedia, kayak
- search for coupon codes on google, they can save you
- sign up to newsletters from the rentacar companies, they spam you with offers all the time
- always order a compact or smallest possible car, then arrive at the end of the day at this carental place and they will probably not have the car that you ordered and they will give you an upgrade
- Downsides of an upgrade, extra gas costs. Maybe your coverage insurance might not cover.
Hope I helped you bon voyage!
Heres a coupon code from the site retailmenot
Here's a link to Hertz Promotions