Marko, have you had luck with the MSPCA? I've met one potbelly pig who lived in Verdun for over 10 yrs but was only allowed because he "Harley Davidson" was used during the day for Pet Therapy at the Douglas Hospital.
The owner had problems once the hospital no longer used him because of the by-laws and zonings. Since pet stores still sell them as pets many municipals changed their by-laws where their now under the "hoof" category making them illegal to own.
But yes they climb stairs and do everything a dog or cat can do. Harley was known to knock on the backdoor when he needed to go potty

Sadly he had to be re-homed but he's not too far away