There is a federal law regarding this. I have one unit that hasn't paid in two years. Letters have been returned and phone numbers are not working or someone else now has that number. I had to contact our lawyer and was told unless you can rent the unit to let it go. The lawyer said we would need a Judges order to proceed with a lien sale. So that unit sits until I need the unit which may be real soon. I am down to 20 of that size left so I might have to spend that money to free up that unit.