About locking cars I haven't heard at all, but I know how to unlock them all.
Here are the codes
<div class="ipsSpoiler_header">
boxer - Enlarged Hands
jizda - Folds roof down on compatible cars
deadguns - Guns and ammo
municak - Infinite Ammo
krefjezivot - Refill Health
parnik - Spawn boat under nearest bridge (Titanic mode)
cumdal - Maximum draw distance
cornufse - Unlock all cars
</div>
See the last code...
Here are the codes
<div class="ipsSpoiler_header">
boxer - Enlarged Hands
jizda - Folds roof down on compatible cars
deadguns - Guns and ammo
municak - Infinite Ammo
krefjezivot - Refill Health
parnik - Spawn boat under nearest bridge (Titanic mode)
cumdal - Maximum draw distance
cornufse - Unlock all cars
</div>
See the last code...