I usually start out by accessing what I've got for a leak. Wash off the transfer at the local quarter wash, hit the bell housing and the lower part of the motor at the same time. Oil migrates, there is always the chance the leak isn't the transfer at all.
Watch your fluids closely. If it's a serious leak and not just a seep, the levels will fall as the oil leaks out. A little oil looks like a lot.
Case leaks can often be slowed down to nearly nothing just by re-torquing the case bolts.
Front and rear transfer case seals aren't that big of a deal. unless the bearings or the bushing are worn, causing the seals to fail.
Sounds like a good job for the local community college automotive shop.
The last time I used the dealership, on trust, they gave me a $400 dollar bill for a seat belt recall. I have no qualms about calling bullchit, when they try to screw me over.
I once refused to pay, the dealership refused to give me my keys, I drove off with my extra set of keys straight to the automobile club. Had them refer me to their mechanic and let him call bullchit. The dealership paid for everything, including my time.