Too bad you smashed the tank. You might have been able to replace that bottom pane with acrylic, if properly supported. It wouldn't work with a side pane, but the bottom would be easier to replace.
Sorry to hear about your bad luck. Glad your hand is still in working condition.
I always water test used tanks before I buy them. Most of the time people will complain they don't have the stuff to do it etc. and my response is I know you have a faucet or hose line I'll bring a python over.
I would take all that smashed glass and dump it all over there driveway or in their yard, alot of small pieces of glass would be pain to clean up in grass..