Sodium hypochlorite sourcing

So I found a local supplier of 12.5% that will pump right into your trailer mounted tank for $2.85 a gallon. They are local, close by, and convenient with no shipping costs, obviously.
What are you folks paying for SH 12.5? I am in Maryland…unfortunately.
And, if they pump to your trailer tank, are you transferring to an indoor tank somewhere?
My garage area hits 100 degrees in summer, how are you keeping your SH “fresh”?

@2.31 a gallon 55 gallon min after searching forever. I’ve been told if I use more than 150 gallons a month that prices drops to 1.66 per gallon. Shouldn’t be too hard since I’m adding roof washing next year. Northeast ohio.