The Bernina 830 and 730 records are in demand. They are great machines! I have my mom's 830 and it's fast becoming my favorite (Sorry Ellie).
I recently found a 730 in a yard sale and am working to bring it back into condition.
Check the nylon gears inside the machine. You turn the handwheel and carefully watch all the way around and look for a crack. Those gears do fail at some point and need replacing, but there are replacements available so it is NOT a deal breaker! Just something to be aware of and a possible thing to negotiate price on.
Good luck! If you can get it, I would so yes, do so!