Taking Best place to buy Swiss Francs using US dollar as an example, the OP asks for the best exchange rates for USD-CHF conversions. I do wonder what added value such questions bring to the site. Even more so if we close them (imho incorrectly) as duplicates of When traveling to a country with a different currency, how should you take your money? @Gagravarr mentions that:
We have lots of people coming on here asking about the best place to change one set of physical money for another sort. Outside of restricted currencies and currencies with "blue" rates, the answer is almost always "you don't want to be doing that in the first place, see this for what you need to do instead". If we refused to close a USD-CHF question as a duplicate of a USD-EUR one because the currencies didn't match, but the advice was identical (don't!), we'd have millions of questions.
As it turns out, we do have a million such questions. Would it make sense to create a go-to question allowing us to close all others as duplicates? Something along the lines of
Where can I get the best exchange rate for my home currency?