A gallon of 35% peroxide is only $60, that’s enough to make 10 gallons of home strength.
(Of course BATF would put you under a microscope for buying 35%, but that’s another story)...
I’ve bought that 35% HP (a little) in the past; but it’s too hard to keep it away from husband grabbing it up and using it like 3%. It can burn like mischief if you get it mixed up with the 3%.