Hi.
If you had booked via Alamo Brits you would have paid £331.50p for the 2 door version, a few £ cheaper but as they dont have 2 door cars in that class I always book the cheaper one! However you are fine with your booking.
No need to show the Brits Guide book, nobody has ever been asked for it. To put your mind at rest there are probably a dozen plus codes to get a discount with Alamo, I have 3 as do a lot of others. They couldn't care less what price you paid, who you booked it through etc. All they want is to rent the cars out and get money!
The car size will be fine but you will struggle on the airport runs with 4 large cases and 4 cabin cases. Pack well and try for 3 cases and they will be ok. Maybe 1 case between the children for a short while?
The 9 year old 'by law' doesn't need a childs seat. It's your decision though if you want to use one. If so take your own as airlines carry them free - well most do.
This is in the
Dibb Guidebook and worth a read
https://www.thedibb.co.uk/forums/Chi...es-p-1521.html
Plus if you look in the Guidebook under travel you will see loads of useful tips ref driving, rental cars, the tolls etc.
When you look on your booking you will see a tab to do online check in. When you have done that it continues and allows you to skip the counter. Not an issue if you cant as its not needed. All you need is a barcode on your online confirmation.
The insurances and other bits such as state tax, airport user fee etc are all in your price. Nothing else needed.
If you can change a tyre yourself roadside assistance is not needed albeit they do sell it. If you want it let me know as us Dibb people know a cheaper alternative that is equally as good and half the price!