Are there any affordable resorts/hotels that have an attached dive shop in Kona?
No
No - several of the big resorts have shore dives - even on-site operators but they're not affordable. The only shore dive you could easily do without a car is the Kailua/Kona pier downtown. There's a couple of older hotels nearby - the King Kamehemeha - it's a Courtyard by Marriott - or Kona Seaside - it's older about a block inland and probably 1/2 the price of the King K.
Jack's shop is about 2? blocks south of there - they also do an escorted shore dive at the pier - and will bring tanks - but their prices are the same as their boat dives 2/$125. The boat dive will be better. Almost all boat dive operators leave from Honokahau harbor north of town so call around and see if someone will pick you up. Or you could take the trolley to their shop/office as an option. Besides Jack's, some of the others are in an industrial park slightly NE of downtown.
The only other shore dive possibilities might be if you could find a cab that would allow you to bring tanks. The three that are possible south of Kona are Pahoehoe Beach Park, Mile Marker #4 or Kahuluu Beach Park. IDK Pahoehoe at all, MM4 is just south of Magic Sands Beach - there are lifeguards there - didn't look like too bad of an entry. Kahuluu Beach is more for snorkelers. It's less than 7' deep for a long way out. Lot's of turtles there - in the water and sunning on the rocks. I assume MM4 means it's 4 miles from Kona.
Scuba Shore Diving Site Listing for: The Big Island, Hawaiian Islands
One thing you might do is call KDC. My buddy dove with them about a year ago. The owner's husband commutes for long intervals (lives near me in AZ) so he's often looking for mid-week dive buddies. They did one site south of Kona with a bunch of spinner dolphins - IDK who drove.
Or even an all inclusive with diving?
None of those either - on either island. Very few resorts even have both an onsite operator and dive. The only I can think of on Maui are the Sheraton Black Rock, the Grand Wailea or the Ritz in Kapalua. None fit my idea of "budget".
No shops are even particularly close to dive sites since all are public beaches - often a short drive in off the main road with limited parking. Most of the dive operators are primarily boat-based as well - esp. in the Kihei area.
I've been looking at the recommended dive shops on the board- Big Island Divers, Jacks Diving Locker, and Kona Diving Company, but I wasn't really planning to rent a car the whole time to go back and forth from my hotel to the shop. What is the best way to do a few days of diving alone in Kona on a budget
IDK either. Everybody charges around $120-140 for 2 boat dives. It's that way on Maui also. I think expenses (and gas) are higher so that gets passed on.
Would I be better off in Maui for what I'm looking for?
Not to
night dive with the Manta's. The only Manta's typically seen off Maui are at one site where there's a cleaning station. But it's not the same as the Kona Dive, the attraction there (for the Mantas) is feeding in all the lights.
Maui might be a little more solo/shore accessible. Shaka Divers runs a dive bus in the Kihei area. IDK if/where he picks up. If you could find reasonable accommodations - that would be the place. [user]Shaka Doug[/user] even has a condo - couple? he's renting now - maybe if they're not full he'd let you have it for a couple days. Ed Robinson's does something similar also.
Maui Dreams Dive Co. also does escorted shore dives - and tank rentals. Most of the other operators in that area are in Kihei somewhere - their boats leave from the Kihei boat ramp daily for Molokini. I don't actually know if there's any affordable hotels there - we stay in condos.
One more reasonable option might be to stay/dive in Lahaina. Extended Horizons is there - they do both boat/shore diving. Lahaina Divers is downtown also. Mala Pier is one of the best shore dives on Maui - you'd walk in just down the street from LD. Tiny Bubbles Scuba also shore dives - their shop is just north of there - so maybe they could work something out also.
There's a couple of older, smaller hotels in Lahaina - one is Lahaina Inn. The other is the Best Western Pioneer Inn. It's a really old building waterfront but is pretty reasonable (for Maui) IIRC. Fly into the West Maui airport from Honolulu - GO, Mokulele or Pacific Air - and a cab ride won't be horribly expensive to that area. There might even be a bus - IDK.
Boat dives from either area run 2/$100-120 From Lahaina you'd likely dive the Cathedrals at Lanai - from Kihei it's Molokini. Although Lahaina Divers also dives Molokini - they've got the big boat for the return crossing - it gets rough when the tradewinds pick up late morning.
For boat dives in Kihei I usually recommend B&B Scuba, Mike Severns or Ed Robinsons. Probably the only one I'm less thrilled about is Maui Dive Shop - they have/had a Kihei boat but their other boat - based in Ma'alea Harbor is fed by all their shops so can be crowded. Sometimes Lahaina Divers can be also - once it was two of us, 4 asian ladies and another couple. The DM took them on an escorted dive leaving us free to do our own the opposite (deeper) way. Probably a bad idea in retrospect, the current was ripping.
hth, Hawaii and affordable aren't often seen in the same sentence.