We like the Evenflo Maestro for our travel seat. It can be used as a harness to 50 pounds and a booster thereafter. it is very light and installs easily with LATCH or the seat belt.

Anonymous wrote:OP here. She only is there for a few months out of the year in a rental, and she won't want to take it back up North with her when she leaves. I guess we could buy a high back booster and bring it with us, but it doesn't seem that much smaller/lighter than his Britax Marathon. He's under 40 lbs.

A graco turbobooster highback is ok for over 30 pounds and weighs a crap ton less than a Marathon. $50 at Target.

Buy a bubble bum

OP here. She only is there for a few months out of the year in a rental, and she won't want to take it back up North with her when she leaves. I guess we could buy a high back booster and bring it with us, but it doesn't seem that much smaller/lighter than his Britax Marathon. He's under 40 lbs.

Its just as cheap to buy one vs. rent. I would not trust a rented seat without history. Most airline let you bring one for free.

Or, ship on to grandma.

If under 40 pounds:
http://www.walmart.com/ip/Cosco-High-Back-Booster-Car-Seat-Quigley/21128091

If over 40 pounds, there are options too.

4? Just have her buy a booster for$40.

Can anyone recommend a place to rent a carseat in Palm Beach, FL? We are going to stay with MIL for a few days and don't want to lug DS's carseat with us on the plane. He's 4, so we would need a convertible carseat. I googled and there are a few options. Did you have a good experience with any specific company?