I said that I wanted to pack minimal for my upcoming long weekend in London and I don't think that will be a problem. I'm not sure about our upcoming family trip this summer. We will be touring Scotland for over three weeks! My mum wanted to check only three big pieces of luggage because everything has to fit into the car afterwards, but I won't be able to add my stuff into those bags because I'm going to take a seperate flight from Berlin. We wanted to book the flight soon, so I have to think about whether I want to check a bag or not. My mum would be happy if I wouldn't take another big suitcase, but I'm not sure I can pack everything in a carry-on bag (10kg + 55cm x40cm x20cm and one additional bag of 35cm x20cm x20cm). She said she would pack towels and other stuff so that I would only have to pack my clothes, but even then I'm not sure. Especially because I think I'll have to think of weather variability. When you add checked luggage after booking it's very expensive, so I have to decide now if I want to add one or not.

What do you think? Is using a carry-on bag possible? Or madness?

ETA

So it's a done deal, the tickets are booked. BUT I'm going to take the
same flight as the family after all (and go there by train on the same
day) because that was less expensive. Which means I can add some stuff
to the bags that will be checked after all if necessary. I'm going to
only take my small carry-on bag all the same and see what happens. I want to do this! And if I can do with less it's all for the better, because everything needs to go into the car in the end.