we are travelling to Porto in a week with kids and we have booked car with one baby seat. My other kid, age of 6 will also need a car seat. I think it's too expensive to rent it (50 EUR), so we were thinking of bringing it along. Where it is possible to buy that kind of equipment in POrto and how much it costs? Simply seat or rack. Where we live, we can buy them in supermarket at about 20 EUR. Any suggestions will be appreciated!