Don't shop around for gas. The government sets the price.
Always check the tire inflation levels of your rental vehicle. The tire shop next to Bonaco gas station on Kaya Industria will check and inflate (or deflate) your tires perfectly for $4.
For serious scuba gear servicing, I go to Hens Silva of X-Pro, though I used to go to Bruce Bowker (RIP) at Carib Inn. Hens brings the tech diver's mind for detail to his work, and I trust him. I buy extra rubber, like hooded vests, at Carib Inn.
Make reservations for Chefs 6-10 months in advance, though many have had good luck with their waitlist. Meals run about $135.00. I reserve Capriccio about 2-3 weeks in advance.
The free English-language newspaper, The Bonaire Reporter, lists the schedules for cruise ships, 12-step and club meetings, and a host of other useful local news. www.bonairereporter.com
Before you visit Bonaire, you'd be wise to check www.seatemperature.info to get the water temperature; that way you'll be sure to bring enough rubber.
My food shopping go-tos: Warehouse and Van Den Tweel for most stuff; Pieterz for what I can't find elsewhere; I only buy meats from Canarbo, which supplies most of the island's restaurants (and they have Nueski's bacon!). The Daily Catch downtown has great fresh fish and prepared seafood dishes; Zhung Kong in the northern hotel zone has the biggest ice cream collection and American frozen foods (be prepared to pay through the nose).
The container ship from Miami comes in every Thursday, so Friday afternoons and Saturdays are the best days to find bananas, American yogurts, and fresh (not aseptically packaged shelf-stable) milk.
ATMs abound. I usually use the ones from RBC (Royal Bank of the Caribbean).
Laundry: Fast Clean on Kaya Gob. Debrot 30 is the cheapest and fastest, though the detergent they use is strongly scented; I take our stuff to Caribbean Laundry Services near the stadium, but they take about 5 days.
Lots of places sell Bonairean salt products, which make nice gifts. When cruise ships are in town, local vendors set up stalls at Wilhelmina Park near the piers; one vendor sells all kinds of flavored cooking and bath salts.
The drugstores I use are Service Drogist in Hato (in the back of Bon Bida) and DA, a Dutch chain. DA has lots of skincare products and some fun European bath and body products that make nice gifts.
There is an urgent care clinic across from the hospital. The graveyard is conveniently located there as well!
If you go to the Donkey Sanctuary, buy cheap fresh carrots at BondiGro on Kaya Industria to feed the donkeys.
I buy good wines mostly from Capriccio, from Van Den Tweel for table wines, and spirits from Bottles.