oops forgot to add to my trip review!

Sofka

I used a taxi I found online by googling "Ashburn taxi" - the woman promised 2 car seats. We agreed that 2 cars would accommodate us and all our luggage better than a minivan.  They showed up and started installing the carseats, and had no idea what they were doing! We didn't have time to wait so we ended up putting the kids on our laps and going that way, Dulles is only about 15-20mins away and it was fine. I asked them to make sure the seats were installed on the trip back. To park 2 cars for 7 days would have cost us $140. The 2 taxis roundtrip ended up about the same, including tips. I would use them again, the convenience was so worth it!

I booked USA transfers to pick up from CUN and take us to the hotel and back. They don't guarantee the car seats.  They had one, we said fine, it was too damn hot to wait and see if another van would become available. The car seat was flimsily installed and had no, I repeat, NO shoulder straps. It was beyond ridiculous.  The kids sat on our lap, it was about a 25min ride to the resort. On the way back, the van had 2 car seats, everything was fine.

We tipped an average of about $15/day, including meals and room maids. 

The trip cost us $5000, including everything.  Kids were free at the resort but we had to buy DD a seat on the plane, while DS was a lap child.