The point I was trying to make was it is more difficult than people assume for SK and NK to reunite. Obviously, as you say, they can still communicate but something that simple has diverged and would need to be addressed, what about infrastructure, media, military,etc....this is all stuff that would require huge funds for them to normalize.
I know, but I deliberately restricted my reply to the language issue.
At present, North Korea has 20 million or so people who are desperately poor, plus a few million who are relatively privileged (though not by S. Korean standards), & a very small number who are well off by almost any standard.
S. Korea couldn't extend its minimum wage to cover the north. At 4580 won (ca USD4) per hour, N. Korean industry & agriculture would be priced out of the market. But nor can it cope with millions of N. Koreans flooding south to seek higher waged jobs.
The great post-unification economic problem would be keeping northerners at home, while finding ways for them to earn enough to be healthy & reasonably content, & building up their country. This would mean a dual economy for a long time, in which the northern provinces had lower minimum wages, etc., made up for by massive subsidies from the south. Those subsidies would have to spent wisely, on infrastructure & education, mostly. Southern & foreign firms would have to be encouraged to move in. Perhaps make most of the many vast army camps available on leases which are free for 10 or 20 years, provided the land is used for businesses employing a certain number of people, with the government paying for infrastructure.
There's considerable agricultural potential, but disastrous government policies have damaged the land badly. There would need to be money spent on reforestation, but happily, this could employ a lot of locals planting trees. giving them a reason to stay where they are.
Roads & railways need upgrading, & telecoms infrastructure is almost non-existent by modern standards, while the south is the most wired country in the world. The physical improvement of transport infrastructure can be mostly done by locals, but they currently lack the skills for installing modern telecoms infrastructure. There'd have to be large training programmes, while initial work was done by southerners. Roll out a decent mobile phone net first, because it's the cheapest way to cover the country.
South Korea makes everything that's needed, so there's a potential huge boost to southern manufacturers. They'd have to be made to locate as much as possible of the expanded production in the north, though, or the inequalities would be exacerbated. Keeping the minimum wage low enough for this while not making it so low that southerners would object to 'cheap labour' & jobs being stolen would be a difficult balancing act.
There'd be a great danger of southerners taking the best jobs up north, while northerners get menial jobs across the whole country. The social & political undesirability is obvious. Therefore, the middle privileged minority in the north could not be shut out completely, however inappropriate their skills & attitudes. The very top, the Kim family & the other leaders, would probably be unemployable, though.
Most of the military are conscripts, but there are also a lot of long-service troops. It could be wise to give them priority in employment in infrastructure work schemes, e.g. planting trees on remote hillsides, & projects which need a larger work force than can be recruited in the area where they take place.
South Korea currently has huge foreign currency reserves. With the need to import raw materials, extra food until northern agriculture can be repaired, & diversion of domestic manufacturing production to rebuilding the north, it's likely that those reserves would be needed to finance trade deficits for several years. So be it.
Government debt is low, so a budget deficit can be tolerated for a while, but there would still need to be large tax rises to keep it within bounds. I would expect huge political pressure on the chaebol to spend some of their financial reserves in the north, to keep down the need for government spending.
Military spending could be cut, but that would only finance a small part.
Things like the minimum wage would have to have an escalator, a gradual adjustment upwards to gradually bring them closer to S. Korean standards, so that northerners wouldn't feel they're permanently 2nd class.