Ok not going to go there about the cable ties,
Anyway for your machine I would do the following,
Change both oils, engine & pump,
Change air filter
New set of valves in pump,
Check the Fuel sediment (tap) trap for any crap from the fuel tank.
If unloader is ok and working then leave it but it wouldn't hurt to change it, keep that one you have a last resort spare.
That's about it for a basic service to that machine