Perhaps a 'passage plan' drawn up on the K.I.S.S. principle would ease your burden starting with the basics:
-boat preparation, vessel hardware (hull, deck, propulsion, openings, standing rigging, running rigging, winches, water tanks, toilet, plumbings, cooking, dinghy, anchors, chains, rodes, warps etc.)
-safety gear (pfd, tether, flares, grab bag, epirbs etc.)
-electricals (batteries, solar panels, wirings, fuses, lights red too! etc.)
-electronics (radios, gps, fridge, plotter etc. But only what one needs on basic level)
-navigation (compass, charts, nav.tools, binocular, hand held compass etc.
-medical (basic medical set, seasickness, sunshine, stingers etc.)
-provisioning
-clothing
And so on. Step by step, systematically...
When you are done, and you still got money and kudos left, go shopping for those bits your eyes are longing for and you can afford.
Some old cruising books would also give brilliat ideas.
Ps: I am doubtful about your bimini holding up
even a small solar panel in a moderate blow.