Re: What items do I need to sucessfully keep my boat in an open slip?
I'm with JoLin--we need a lot more info. Tides, wave action, pier type? Boat type? How well supervised is the pier and how far away are you?
Forget the solar and the trickle charger, if you have a good battery. Just check it every week or so--and run it.
Forget the fenders; tie the boat off the pier (unless it's a floater with zero wave action).
Talk to the dockmaster and others nearby on how to tie up. With tides it can be tricky, and fatal (to your boat).
As for covers, depends on the boat, and your climate. Covers on the whole boat can be a pain on a wet slip. Unless you have the kind of boat that's not made to be left outdoors, you might not need to cover much. For example if it's a center console, get a cover for the console and remove the cushions. Look around your marina and see what others are doing. Also depends on how much you use it--cover it if you are leaving it a long time. Where I am, few people cover the whole boat, and those who do have sofa boats that don't weather well.
Also, would you pull it out if a big storm system was headed your way, or leave it in? Do you get those afternoon squalls?
How about security--can you leave stuff on board? some stuff? Do you need to lock anything?
I like a battery switch that cuts off everything except the bilge pump. It saves on corrosion and drain from the inevitable small shorts, prevents a big short/fire (BTDT).
Hide a key on the boat, so it will be there (a) when you leave yours at home and (b) you need the dockmaster or neighbor to help out in an emergency. In fact, see if you can get a storm buddy system with someone else there that you know or feel like you can trust. Boaters have to look out for each other.