Metric and standard? That's what Crescent wrenches are made for...;^)

But seriously, if you can, do an inventory of the sizes of nuts and bolt heads and either put together a kit of sockets and wrenches needed or get a pre-assembled kit in both metric and standard (SAE) sizes. Don't forget the extensions.

I'd probably have a 1/4" as well as a 3/8" kit onhand and limit the 1/2" and larger ratchets to those sizes that are specific to your needs. There are adapters that will allow you to mix and match some sockets but be careful of putting a large socket onto a small ratchet, the torque needed might be too much for the ratchet.

Those combo screwdrivers are really handy, especially the ones that can also be used as nut drivers.

The Gearwrench setup above looks really handy but I don't know if the metal quality is any good? Presumably it is if Falcon5000 uses them in a commercial/work setting.

The hand drill is a great idea, we've gotten so spoiled with rechargeable portable tools that we forget about the truly manual stuff sometimes.

I'd definitely get some Liquid Wrench or even better, the PB Blaster penetrant for sticky nuts and bolts. And those Knipex pliers are just the cats meow to a tool guy like me, I haven't convinced myself that I need them badly enough yet but I've used them and they just flat work.

hmmm...what was that website again...?

JohnE

P.S. get yourself some silicone "rescue tape", great stuff and it's even available at Harbor Freight.