I know there are no hard and fast rules on writ vouchers because it depends on the economy and the platform.
Does anybody on PS4 EU have any kind of guide as to when its actually worth doing them? For example is a blue jewelry writ voucher for 5 writs worth doing, or a purple one for 20 worth doing? What kind of baseline returns do you need to make them worth the expense of doing them? I have a crapload in the bank that are old/new. I was just wondering what ones I should destroy/give away or which ones I should keep and do.