You can only register lorries that:
were acquired between 01.04.2004 and 2016 (via purchase, lease or hire purchase)
for purchase and leasing you can register trucks whose initial registration took place for your company (thus, were “new”). For hirepurchase you can register vehicles, which had the lessor as the first registered owner and the mileage was less than 700 km at the beginning of the rental period
were heavy or medium (from 6 tonnes)
It is irrelevant whether you later – after own use – resold the trucks.