Which cars are good to buy above 50K mileage?

I would like to know which cars will run fine after 50000 miles. I heard only Japanese and German cars (like Honda Civic OR Toyota Avensis) are good after this mileage. is this true? but they are very expensive. what about Ford Mondeo or Focus OR Vauxhall Corsa/Vectra OR Renault Clio/Laguna. are these cars not reliable after this mileage? these are a bit cheaper compared to Japanese or German ones. I looked for used car ratings, but there is no mention of mileage in it.