It is SO simple to do and CHEAP if you get the parts mail order.
Example; I put a set of 4 pairs on a Kukje tractor for about $500 a few years ago.
Prices of Prince valves haven't done up much since then, according to the various catalogs.
Why 4 ?
Well, a hydraulic top link takes up one for starters and it is worth making that a floater (was for me, your apps may be different).
The stump grinder takes two more, leaving one for a
grapple.
You almost can't have too many, but ONE will almost certainly not be enough.
If you get the Prince modular valves you can always add more sections - just use 3 longer bolts.
Here's a tip;
Use a male and a female on each outlet pair, e.g. the outs are all male and the returns are all female.
Similarly use one male and one female on each implement hose pair.
You will ALWAYS couple hoses up the same way, i.e. no mistakes because left and right or up and down have become reversed due to plugging in differently.
You also buy male/female pairs every time you get an implement and they're cheaper that way.