Since you NEED the money and are ok with selling either of the 3 I'd say sell them all, get your Bill's paid and by the time you've saved up and are ready to buy again think about which of those knives you miss the most. If any at all. By that point you may feel like "hey, their gone but I'm ok with it". In that case you get to have fun shopping for a totally different knife and get to try something new. If that's not the case and you regret selling one that's the knife you want to get again.