I have a cat with diabetes-- he was diagnosed in Feb. of last year and has been on and off insulin since. 
I was TOTALLY freaked out about money in the beginning but it really hasn't been too bad. We do the glucose testing at home (again, not as traumatic as I thought it would be) so we don't have to take him to the vet for checkups.
He was on Vetsulin before it was recalled- now he's on Prozinc. I know that Vetsulin would lose potency after about a month, but every insulin is different. Prozinc, for example, can last for a year (according to their website) and we've been using the same vial for 3 months now (our cat is on a smallish dose).
We get syringes from WalMart, FAR cheaper than the vet ($12 versus $30!)
The only real bummer, moneywise, has been vacations. Instead of having a catsitter come every other day to feed and change out litter, we now have to get one to come twice a day for feeding (only canned food now, low carb) and insulin.
Please feel free to PM if you have any more questions, though I second the recommendation to check out felinediabetes.com. The people on the boards there are really helpful.

I was TOTALLY freaked out about money in the beginning but it really hasn't been too bad. We do the glucose testing at home (again, not as traumatic as I thought it would be) so we don't have to take him to the vet for checkups.
He was on Vetsulin before it was recalled- now he's on Prozinc. I know that Vetsulin would lose potency after about a month, but every insulin is different. Prozinc, for example, can last for a year (according to their website) and we've been using the same vial for 3 months now (our cat is on a smallish dose).
We get syringes from WalMart, FAR cheaper than the vet ($12 versus $30!)
The only real bummer, moneywise, has been vacations. Instead of having a catsitter come every other day to feed and change out litter, we now have to get one to come twice a day for feeding (only canned food now, low carb) and insulin.
Please feel free to PM if you have any more questions, though I second the recommendation to check out felinediabetes.com. The people on the boards there are really helpful.