[onetwo_threefour]

I'll second what Mike says, but really the issue of whether there is a personal guarantee really is the critical one. There is not likely any other way they can come after you personally outside of a provable fraud.

You might ask around with others that have Commercial accounts and who may still have their original paperwork to see whether a guarantee was in place.

Another idea... in Alberta a gurantee is not valid unless executed with a
Notary Public signing a certificate pursuant to the Guarantees Acknowledgement Act. As such, if you never had to go to a notary to set up your account with Home Depot it's likely that there is no enforceable guarantee.