I was wondering if it was preferable to have one suit for both Shabbos and Yom Tov or to have two different suits. And can you wear Shabbos/Yom Tov suits to other occasions like Bar Mitzvahs and weddings? And if minhag is applicable in this situation I would like the general Ashkenaz opinion.
The S"A 529/1 writes that one should have better clothing for Yom Tov than Shabbos.
ובגדי יו"ט יהיו יותר טובים משל שבת
The Mishneh Berurah 529/12 writes that this obligation is only if one can afford it.
בגדי יו"ט וכו' - משום דחייב בשמחה, וזהו ג"כ בכלל שמחה. ופשוט דכל זה ג"כ בידו משגת:
I personally do not know many people that have special Yom Tov clothing.