@tinkoivan
There's no need to load "unofficial" unlocked maps to it. It has an LM entitlement for EU and as i said Garmin doesn't enforce the first stipulation usually and that's even if the original owner hasn't removed the registration in his name. In fact if you load the device to GarminExpress but skip the part where you register it, you can update maps for it's lifetime. Just don't complete the registration, leave that page blank/unchecked and click 'Next' to proceed, unless the previous owner first removes his registration:
Spoiler: Image
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