Another twist, one that I prefer, is park anywhere other than a reserved spot (generally paid for in some form and the vehicle will have some sort of identification). Park in a reserved spot and the vehicle is towed.
MG
"There are two ways of constructing a software design. One way is to make it so simple that there are obviously no deficiencies. And the other way is to make it so complicated that there are no obvious deficiencies."
Tony Hoare
"If you think it's expensive to hire a professional to do the job, wait until you hire an amateur." Red Adair.