I rent a garage from Hounslow council and I can confirm that they do charge more to private tenants than they do to Council ones, and it is more than the £14 per week stated. However they do not stipulate that the garages can only be used for storing cars. In fact most of the garages in the block where I rent one are used for storing everything except cars. The Council are very quick to chase the rents on these garages, but if it comes to problems with access due to illegal parking and blocking entrances, they just don't want to know, stating that you rent the garage but not a right of access to it.
Angela Parker ● 5228d