Welcome to the forum and jet boat ownership! In the infamous words of
@Brmorganjr , BEER! Of course that is a consumable, much like gas, but it is a necessity almost! You didn't mention whether these were mods, equipment, or accessories, for your top 5 items. That kind of matters, because as you can see, the list is developing in both directions. So you kind of need 5 top mods and 5 top tools, maybe 5 top toys and 5 top accessories. Some of these things kind of cross lines being a mod but an accessory as well, like a box anchor. In my opinion, the box anchor is the single best thing I have on my boat. It is truly a set and forget anchor once you understand the principles involved. The direction you go with other things kind of depends on how you boat. Some like to lounge on the boat, such as at the party cove or sand bar, others anchor in deeper water, and others don't do much of that and find themselves doing wake sports and then coming back to their dock. So the list develops based on how you "use" your boat. Here is a valuable thing for the new owner, it is the "checklist". And the checklist can be modified to suit the way you use your boat. I keep my boat in the barn (second garage on my property). So my checklist evolved from that approach, rather than someone that has a boat on a lift in the marina. But it was created in Word and you can modify it to suit your needs. A checklist is a "check" list, not a "do" list, but when you are new, a checklist can teach good procedures and "flow" or literally a routine. It is the routine that you develop that works, that saves your butt at the end of the day. So I will give you the checklist and with it, you will come up with what you want to add to your top 5 lists that work for you. You MUST have the required coast guard items plus what you need to operate your boat safely. Good fenders, dock lines, spare rope, plenty of rode/chain/anchor depending on what anchor you choose. The list goes on. Mods? Well, the stereo upgrade is a must, and a new owner may want fins to help him develop and teach the boat to family members. Storage containers and even storage mods to help store containers and other stuff. Our head compartment has been modified own both of our Yamahas to have shelves. And they were so useful that Yamaha adopted them and added them to the new boats. Additional lighting for night time fun is great. The AO Cooler is an absolute must IMO. The 36 can is a good balance, the 48 is too big and I have had two 24 cans and they are too small unless you have two of them. Back to the ground tackle for a moment...the standard deep bow anchor I mentioned, I prefer the Slide Anchor's Box Anchor in the small, it is the appropriate size for our boats and will fold and fit in your anchor locker...but pad that locker and keep the anchor from bouncing as it is heavy and can crack your hull and gelcoat. But as some mentioned, the stern anchor is another important tool too. Depending on where you anchor and play, the stern anchor can be set on the beach/shore, and the bow anchor is out deeper 50 feet or so in front of the boat, and then you can enjoy the wonderful swim platform right next to the beach in ankle deep water. The same company that makes the box anchor makes the Shore Spike, and the shore spike is a well suited hammer style spike that is easy to use in all kinds of conditions, even underwater! You need a large shore spike, as the smaller one is too short in loose soil conditions and not a big enough hammer to drive it into tight soil or rocky conditions. Then, to hook some of the things you need to hook, some good carabiners are helpful. But NEVER USE A CARABINER ON YOUR PRIMARY ANCHOR! Ask me how I know. Anyway, your off to a good start. Hide the second set of keys with floatation in the boat somewhere. Get a good boat bag too, the more waterproof the better. Never have your car keys in your hand walking to or from the boat over the water, and get some croakies or similar lanyards for glasses! Once again, welcome aboard and here is the checklist!