It's been years since I have needed to ask, but in the past they have agreed to accept a check dated for Friday of that week (when they banked). I believe euthanasia depends on the dog's size and weight and how much of the drug is needed. I have experienced them agreeing to bill me for that procedure, but we've been with them for decades and always paid them. You can email them from their website.
Best bet is to call them sorry i don't have that answer and extremely sorry about your dog
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