Parking on my own private land

[dlp01]

I have a driveway that will hold 10 cars. Most of the time i have 6 cars parked on my drive. My husband is in the motor trade so we drive a different car each week. All of the cars are registered to either myself or him but i have been told by the council that i cannot park that many cars on my drive. They will not tell me how many cars i can park but have said that if we are caught trading from the drive which we arent then we will face a �20k fine. How can this be right if one of us owns all of the cars