The six of us spent 22 nights on three islands in June. I never really added it up, but we probably spent in the neighborhood of $6500 total.
We used timeshares for all our lodging. I usually estimate about $100 a night when all my fees and memberships get added in, though it's often less than that.
Four of us went on ff tickets. DD had someone drive her to Atlanta (about 250 miles away) because she found a great fare of around $350 roundtrip. DS18 dilly dallied, so his ticket was more than double that.
We spent about $1000 total for the rental cars, searching all the codes I found on Mousesavers and anywhere else I could think of.
Our interisland flights added up to several hundred dollars.
We joined Costco because we heard they had the cheapest gas on the Big Island (they did) and also used the card for groceries, scuba gear, you-name-it on two of the islands. I hear Kauai is getting a Costco soon as well, but we used
Walmart for now.
We didn't do any of the expensive tours, but saw a lot of stuff just driving ourselves around. I'm sure there were things we missed, but we stayed very busy.
It was the trip of a lifetime and the cost was not burdensome. Be creative and spend lots of time on the web searching for deals. They are definitely out there. If we could have traveled a bit more off-season, we could have made the trip quite a bit cheaper.
Sheila