I don't know the answer to your opening question, however as a Belfast native, I think you would likely have great difficulty in getting a 3 year old car MOT'd here at present.

As you may know already, MOT centres here are government run, and not the responsibility of local garages. Early last year, a problem was discovered with the vehicle lifts (cracking in the scissor mechanism, something like >80% of lifts affected) and as a result MOT centres were closed to enact repairs with temporary exemption certificates (TEC) used to cover cars affected.

Fast word a few months when the Covid pandemic hit, MOT centres were repurposed as drive through covid test centres and vehicle testing capacity was greatly reduced. Only certain categories of vehicles are eligible for test at the moment, basically cars coming up to 4 years old, public service vehicles, and vehicles who's TEC has run out. Everything else is getting a TEC (got a whole year added to mine). Link below.

Coronavirus (Covid 19) and motoring | nidirect

I imagine cars between 3 and 4 years old travel across from here to Scotland on the ferry all the time, cant see you running into difficulty if you were to bring one over.

Hopefully someone else reading will know better.

Regards,

M

edit: forgot to mention, if you are buying from a dealer, you can get them to tax it on your behalf as a new keeper, which should at least save you that hassle.

Edited by moward on 29/03/2021 at 16:02