[little jeremiah]

I’m sure that whatever materials the barriers are made of, and may be different in different locations, they will be carefully maintained.

[JockoManning]

I'm NOT so sure the wall will be carefully maintained everywhere. Political & economic winds change--sometimes at a frightful speed.

Then there's two countries--currently--involved. One of which has more investment in destroying a wall than in helping maintain it.

I'd vote for the minimum maintenance needed sort of wall.