Question re: Cashing in Cards

When you eliminate a player and usurp his/her cards, do you need to have at least 5 to cash them in immediately or can you simply cash in a set regardless of how many you have in total?
I know that if you have over 5 cards but more than one set that you may cash in both sets.
I know that if you have over 5 cards but more than one set that you may cash in both sets.