I'm happy to be corrected, but I'd suggest wet-lease. My reasoning is that clubs, schools, or whoever you hire from will normally buy "bulk" fuel at a reduced price. This is, to a degree, passed on to the customer.
Dry-lease, I very much doubt you'd be able to secure such prices from so many different FBO's, as you'll only be picking up 100 liters here and there... Unless you secure some hose-pipe, an airfield full of filled up aircraft and some Trebor soft mints...
