So I got back last week but haven't had time... I'll add and clarify a few things up to date as of 2/16-20

Entering - fixed taxi rate of 25 US from int'l to ferry terminal
Ferry to caulker is 25BZ r/t, 30 is also possible (and 20, but i only found out afterwards and still don't know how to do it)
Tom's Hotel was 19US/night for a room w/ 3 beds and a shared bath. A casita was 30US/night w/ 3 beds and private bath. Either are good options whether sharing a room or not. Very clean. Talking to people staying at miramar, the hostel, and daisy's it sounds like Tom's Hotel was much cleaner. Very basic but it has its own dock..
Wish Willy's was worth it - just ask for what's good. He's a professionally trained cook that now lives in CC 6 months/year.
Jolly Roger and Frans also the same. Since drinks were "included" but too weak for our tastes, we bought a bottle of 1 barrel rum and they had no problem with us doing so.
Salbutes from the mexi place on front street are cheap cheap cheap and great.
The ham/cheese thing at the bakery is worth waking up for and costs perhaps a dollar. Other items there also worth it - very cheap.
Rasta Pasta is closed, in its place is a bar not really worth mentioning other than it has free wifi.
The sports bar also has free wifi.
Bottles of rum are about the same cost on the island as off (~$9US for a 750 of decent rum) and cheapest at the chinese market on middle street. Get one of those and a box of pineapple juice and a cup and you're good to go.
Diving I couldn't get any discount other than a free shirt... was just over $100US for Hol Chan 2 tank dive and just over 130US for turneffe 3 tank including lunch - which I thought was a great deal overall.
The various markets will have anything you need and other than things like bug spray the prices aren't as high as you would expect.
If you put bugspray on your ankles and feet, don't forget the bottom of your feet
Leaving - taxi from ferry to intl was 40US for 5 people - I think we got screwed and should have been charged the flat 25, but wasn't paying attention..
I couldn't imagine doing a day trip to a maya site from CC... you'd spend half the day traveling uncomfortably.
San Pedro from a distance when on the water looked too big, am glad I was on CC.
Departure from airport was 37.50US cash or credit, didn't matter what airline you were on.
Duty free I thought was nothing exceptional - could buy at the same price either in belize or guatemala, in some cases cheaper. Marie sharps hot sauce was 4 or 8BZ depending on size and type.. only slightly more than non-airport. They give change in US, so no worries there.

I was in guatemala as well, and they did not credit the exit fees previously paid (it was ~19US leaving by car).. guatemala entry and exit fees were approx 1.30US. Zacapa rum was cheaper in guatemala than bze duty free.

hope that helps someone..