I've a 67 plate 1.4 Avant S Line - kids were 4 and 2 when I got it, 6 and 4 now. Rear seat space absolutely no problem for the kids, loads of space - I'm 6' and do the majority of the driving, the 4yo is behind me but the 6yo could be with no issues. Boot space - generally fine, but it's not massive.
I'm in London - in August we did a week in Weymouth, a couple of days in Gloucestershire then a week in Scotland. We had to take beach wear and wet weather gear, but could have got clothes, food, games, books, entertainment etc in there. Wouldn't have fit in bikes but did manage two scooters and helmets.
For that trip we also had to take a king size duvet, two singles, 6 pillows and sheets and towels for the family - no way that lot was fitting in as well, so had to get a roof box, but that was the first time in 3 years we've needed it. Roof bars and box I got will have space for two bike carriers which I'll probably have to get next year as they outgrow scooters and use bikes more often.
For weekend day trips I can get both their bikes in the boot at the moment - one with 16" wheels and one with 14", with the load cover on. Eldest goes up to 20" wheels at Christmas, and I don't think they'll fit then, so I'll either have to go with roof carriers or possibly just go without the load cover, will have to see how that one works.
Any questions I haven't answered, shout!
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