You didn't mention the brake controller ... You need one that works.

A trailer aid is good to have to change a tire, otherwise you'll have to unload the horses.  A dangerous operation, on the side of a road.  Of course, a couple of planks works too and is a lot cheaper.

Depending on where you are keeping your trailer, you might want to get a hitch lock to keep someone from driving off with it. If your tack area doesn't lock, you may need a lock for that. Another thing I would suggest is a water jug of some sort. I bought a 6 gal water jug in the camping area at WalMart and it's pretty flat. I attached rings to the trailer wall inside the tack area and bungee corded the water jug to the wall.

Congrats on your new trailer !!!

Congrats on your new trailer. 

Just something that I have seen, sometimes ramps when lifting them, the sawdust or poo get stuck in the ramp closure and people bend over to clean them out... Right at the horses hoof level... I would suggest just purchasing a cheap broom to store in your tack room, to also use on that and in the tack room itself.

Does it have mangers?  If you haul with hay, I would get the nice hay bags (not net material) the more solid ones.  Ties for the inside of the trailer to hook them to.  I would also stock up with snaps/buckets and such just in case.  You can never have too many snaps, rope and chain! 

I would also make a first aid kit to store in your trailer for human and horse.

I love my "tire buddy" not sure exact name, but you drive up on it if needed, it can also double for a step into the DR if needed!  :)  I have not used mine but the first time I go without it.... I prob will get a flat! 

Ghgirl & Krys have some excellent ideas.  I also keep haybags, water buckets, bucket hangers, extra halter & lead rope, bridle, saddle, extra parts for equipment.

Some others things I keep are an extra set of clothes, boots, rain gear, fly spray, hose to rinse horse off, electric cord, flashlight, fire extinguisher.

Sometimes we ride in cold weather so I keep a warm blanket for the horse for after riding and hauling home.  Have fire starter and matches in case we want to build a first to warm up.  In cold weather I keep tea & hot chocolate.

I travel with my horses so I also have a trailer aid to drive my trailer up on to change tires.  Also had the experience of not being able to get the tire off the trailer so since then I carry a block of wood just in case I have to unhitch the trailer and leave it.  Also leave an extra heavy duty tire wrench in the truck to help with loosening the lug nuts. Be sure to check your spare tire as well.

I had my vet help me put together a first aid kit for the horses and I have one for the humans too.  Check your first aid kit yearly because vet wrap can get old etc.  I keep a womans pad and a baby diaper in my kit because I had a injury once that cut through two muscle and an artery and it took a diaper to be big enough to cover it, suggestion made by my vet.

Happy riding!

Yes.. I'm having my first driving lesson on Monday with a friends smaller trailer.  At least it will get me started. I have already enlisted another friend to spend a Sunday AM with me in a parking lot to work on backing up skills.  Right now I'm trying to figure the best way to drive the trailer home (North of town and I'm south) I'm not sure round the beltway is the best way to start, but might be better than 2 lane roads with traffic and construction.  I'm planning ahead... ha ha.

nice.  a flare bouncing off the hood of oncoming traffic will sure get more attention than a triangle, which is all i have....now i feel undergunned, thats a little unusual.

I bought a rechargeable lantern and it has come in handy for finding things in the trailer/dressing room when the lights aren't hooked up, hitching and unhitching at night.

Also a muck set: folding wheelbarrow, shovel, broom, and fork for cleanup.

A nice washable rug for your dressing room entrance.  A small wastebasket is handy.

I hung a flat organizer on the wall with clear plastic pockets that holds bungies, fly repellent, sunscreen, leather punch, umbrella/plastic hat cover, gloves, compass, matches, etc.  Easy to find stuff.

I always try to keep a "tool kit" in my trailer with the proper things, flashlight, screwdrivers, hammer (never know) and wrench, wire cutters, knife, you name it!

Have you seen those collapsable trash cans, that is my new purchase, they are great, it collapses small and you just pull out and boom it popps up, but a trash bag in and you are good to go.  :) 

I have a rug when I walk in the trailer that is washable.  I also have indoor/outdoor rug for outside the trailer that is bigger to step on and get a lot of the "stuff" off before getting in trailer, OR to take shoes off then step on the rug then inside the trailer.

Extra halters and extra leads, a lunge rope (also doubles as extra rope to tie stuff down) and even a horse first aid kit.  Ace/Rompin/banamine/bute/needles/syringe and thermometer and stethascope.  Print out the standard "sheet" of what the horses normal temp and heart rate should be and keep it in a 1st aid kit to take with you in your trailer.  Don't forget vet wrap, duct tape and baby diapers.  Also a first aid kit for you too don't forget!  Ice packs - the kind that you break and shake, have used them on me and my horse before.

Hope that helps to give you more info!

{SLAPS HEAD}  DUH... I forgot that major detail! 

thought I'd add my .02.  this is a great thread.

A tension rod for handing clothes is SO handy and Walmart has a hanging shelf (velcros over the rod) made mostly of fabric, it's light and has 6 shelves. Great for holding all kinds of stuff, towels, helmet, clothes, etc. 

That pop-up idea is a good dirty clothes hamper, too.  Helps loading/unloading the trailer.  Put the clean stuff in it and it's ready to put back in the trailer. 

Muck boots that go on/off easily are a must.  As is a sharp knife for emergencies.

The money tip was maybe the best one!!

YOU NEED A BRAKE AWAY BRAKE SYSTEM. Remember to get one with a charging circuit and a charge indicator to keep the gel cell charged, and let you know it's charged befor you head out.