Hi there, I am new to the forum so hoe this is in the right place.

What type of beach is it? You might want to look at a cheap reliable 4x4 (LRover, Bighorn, Pajero) as an alternative. Road legal, with lights etc, good brakes and probably around the same $$

Don18025 asked the real pertinent question. How much are you able to spend ?
I originally had a little Iseki 17HP (HST) and it worked wonders for my little Ali Pontoon boat. When I upgraded to a 6 mtr boat, it was straining its ring out going up our hill ~ also about 20% gradient.
I traded up to a (Compact) 30 HP Kubota and this eats up the job. I don't even need to change to 2nd ratio.
My mates all thought I was nut's spending between $5 & $10K on a tractor.
My argument was that I was getting modern technology and I was able to "realize" the resale value out of it pretty easily. The argument was proven when I came to upgrade. I actually traded my smaller tractor on the larger one & traded it for the same price as I had paid some 30 months earlier !
Both of my tractors had TURF TYRES on them. If you are launching into mud ~ they will not be for you, but on sand ~ they have proven to be awesome. They are also great on my section. Lugged tyres rip up the grass when turning & manoeuvring. Not so, the turfs. I like the idea of 4x4 and diff lock is a must. Most of these features come as standard on modern tractors. Just steer away from "modern" Chinese ones. Parts will more than likely be a problem.
Purists will not agree, but I love my HST. It also allows novices to be able to use your tractor.
If you have a tray fitted to the hydraulics (as opposed to an immediate tow-ball) ~ it means that you do not have to go as deep into the water to launch. It also increases the height to which you can raise your trailer to "slip" the boat.
Oh.... and did I mention "Petrol" ? Stay well away from it.
Just one man's opinion !

Diesel yes.

Good info red89..

I have a for 4000 galv rims recent repair etc may look at selling for around 7 k

The beauty about David Browns is that the final drives are offset, so you can turn them one bolt hole increasing rear ground clearance significantly, keeping everything outta the water. Requires an extra step welding on to get up on it after doing this, but gives huge benefits in keeping the salt water out of the brakes and all linkages etc.

Id look for 1 around 50-60hp with wet brakes. The 1st 1 I bought was from Big Manly beach, the guy demo,d it towing his 6.5m boat , on flat beach. It struggled to tow it up the hill from the beach to my home, It was a MF 28, brakes fail after they get wet. Up graded it to a JD with oil brakes, goes really well, well worth the $3500 I paid for it

I have a DB770 goes a treat, has been well maintained, I wash it then spray with Salt away, no issues with the brakes at all...mind you I travel on the flat towing a 6.5HT tinnie...never been close to bogging in the sand but then Manly is pretty firm, haven't noticed about the increasing ground clearance, might look into that...