This is frankly insane and, yes, Keltham should've checked that before spending a lot of time on scroll practice, though it's probably good Spellcraft practice in general.

Is there a loanable magic-item Keltham can rent which would let him cast a few Major Images?  For that matter, what was the rent-price of Goggles of Detect Magic, or of Arcane Sight, now that Keltham has any money?

This is frankly insane and, yes, Keltham should've checked that before spending a lot of time on scroll practice.  Though it's probably good Spellcraft practice in general, since it lets him keep going past his daily wizard magical capacity.

Is there a loanable magic-item Keltham can rent which would let him cast a few Major Images?  For that matter, what was the rent-price of Goggles of Detect Magic, or of Arcane Sight, now that Keltham has any money?