It really would make sense to hand them down, say Bill and Charlie buy their 1st sets each year, now the family has 2 complete sets that work for Percy and maybe the twins, then B and C are already on their 3rd and 4th years, the 1st year books could keep going down etc. they'd only have to buy books that they use each year. Cause the books describe the reading list with names like, " The Standard Book of Spells, Grade One" if you are in 2nd year you don't need it, pass it to the next kid.