*shrug* there are variations - if you happen to have Epic Leadership (or even just regular leadership, but qualify for Epic Leadership), and lots of wizard followers, then you can get them all together and make it a ritual spell, and bring the final DC down all the way to 0 (at Epic Leadership Entry score 25, you have 135 level-1 followers and 13 second level followers - if all are good wizards, you have 148 level-1 spell slots for -148 spellcraft DC; 7 3rd and 4 4th, for 11 2nd level spell slots and another -33 DC, 2 5th and 2 6th for 4 3rd slots for another -20 DC, 1 7th level follower for a 4th level spell slot and another -7 DC for -208 from ritual alone; 10 extra minutes makes another -20 for -228; if your cohort is a wizard as well, a 9th slot from him or her makes an additional -17 for -245; clear a DC 3 (one day, 27,000 gp, 1,080 XP to develop, 11 minutes (well, after the headache of bringing all your followers together on the same day) and you can get that Self-Only permanent immunity to standard forms of dispelling)(thus, spending NO XP at all, in 11 minutes) for a spell that is otherwise identical to the one above. If you can convince another party spellcaster (or even a hired hand, or maybe you have a leadership score over 25) to help you out with a 2nd level spell slot, you can reduce that further to DC 0, 0 xp, 0 gp. It all depends on how much trouble you want to go to. Then consider that the same technique that brought that 248 DC down to manageable levels works for any epic spell with a permanent duration - you can transform yourself into, say, a Young Adult Gold Dragon (for minimally epic level 21; you can still revert to a human form with it's supernatural ability to do so). You can also use the same technique to get +5 inherent bonuses to all base stats, or whatever. Granted, Epic Leadership to reduce the DC is rather munchkiny, but careful use can make Epic Spellcasting far from useless ... if pretty much limited to permanent buffs for a long time.