Cabrio with softtop?

Moin people, I would like to get a new car soon it should become a coupé or convertible with convertibles I have imminent still a little pain since most have a softtop (e.g. 1er). That’s problem because I don’t have a garage but my car always stands outside. And I ask myself the question is a convertible with softtop useful? And can you possibly convert to hardtop and how expensive would that be? Thanks already in advance With kind regards Chris995