Whether or not a homeowner's association can "boot" an owner's car for unpaid dues is best addressed in any recorded "covenants, conditions & restrictions" and all other approved rules and regulations by the homeowners.You need to read these documents carefully to see if booting your car was allowed and issue a decal for past owed dues. Likewise I would ask the association in writing for the authority for what it did.It sounds that you need to consult with an attorney experienced in association issues. Good luck.