sorry this is a long one!
Here in belgium you have to test your vehicle if you sell it (that test lasts for 3 months) then you have to renew again if not sold, and so on.
the new owner then has to test it again (that lasts a year & must be renewed yearly) for his ownership.
old timers ("classic cars") if its a car, then its 25 years old, if its light comercial (van, pick up etc) then its 30 years old, you can take them for a normal "mot" and need it every year, anhave no restrictions, but if you go for an old timer "o" plate, then its 1 test, thats it, but no driving at night, your limited to a 25 mile radious, unless its for a pre arranged event.
but i've seen some old timers come in to work that are only fit for scrap.
the test stations are a huge drive through affair, and in my experiance, because they are private they do it for the money, we take cars/trucks all time and from one test to next there does'nt seem to be the same testing, unlike u.k have the guideline from the testers manual, so normally "all" testers follow the same tests.
and for trucks, if you go for test and fail on certain safety things, i.e brakes, you fix them and once re tested, it only lasts for 6 months, if you fail the re-test again, fix them,then pass, it goes down to 3 months! (its just a money making system)