Managing all the trivials of buying a second-hand car

So why am I struggling so much? To be fair the old faithful 07 Ford Mondeo has barely complained as it has had its wheels knocked off kerbs, its backside smacked into unseen bollards, and its upholstery used as a playmat, place-setting, and vomit receptacle by overzealous children.
Its cavernous boot has been tested to the maximum, initially with buggies and high chairs on the slog from Cork to the in-laws in Belfast and Galway, and later with scooters, skates, bikes, and boots. That huge carrying capacity is playing a huge factor in the quest for a successor.