I Think what Harry meant by that idiom was, if you buy an ugly car or house etc, it will be harder to sell when you come to sell it than a beautiful / smart / tidy one.
Ah, OK, that makes sense ...it's, because I know so many people who, when buying cars, spec them in a way that they can sell them "better" after some time. I guess, that's why we see so many silver cars over here.
...it's, because I know so many people who, when buying cars, spec them in a way that they can sell them "better" after some time. I guess, that's why we see so many silver cars over here. 
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