So I was playing through omega ruby and alpha sapphire, and I realized something with the secret bases. If they have holes, you can just cover them up! However, I haven't found anything to cover up the holes in my secret base, so I can't really get across to another side. I'm sure there is a way, I just don't know.
Anyways, there should be a board item after the Elite 4 in Hoenn in the "Lilycove Clearout sale" where there are different rare decoration items each day, just like in the original Ruby and Sapphire.
Thanks for reading ;D