Ha…I'm with ya on going overboard!  Boondocking like my wife and I do, we have to be self-reliant.  I always keep my 18v Milwaukee cordless tools with me in the truck and at the least, I highly recommend a cordless drill with various bits and fasteners.  I always have some Tek5 self tapping metal screws with me and with a scrap piece of flat bar, I can band-aid any broken weld on the trailer.  For about $20 you can buy a nice set of nearly every bit…phillips, star, hex, torx, etc.  Pretty handy to have…especially with the low quality of RVs now days, I'm always having to tighten something or add a screw.  And of course, duct tape and a small roll of bailing wire.  I was on nuke subs in the Navy and you'd be surprised at how much of a sub was repaired with duct tape.

I live this world.  All the way down to "if I needed to borrow it three times then I simply need to buy one", and it isn't that folks won't lend it to me again.  It simply shows that I need to own that tool.

I have my tool kit broken into sub-kits.  There is a kit in each vehicle that is dedicated to that vehicle.  That kit involves a somewhat universal socket set/wrench set/hand tools plus the oddball large sockets need for that particular vehicle's transfer case fill plug or axle nut.  But then I also have the traveling kit which I move from vehicle to vehicle as trips dictate.  That is the kit that contains a scanner, fuel pressure gauge, multimeter, sets of gearwrenches and other things that are a bit too costly to own in multiples.  Or at least own in multiples that correspond to my multiple vehicles.

I carry the torque wrench in my kit too. It is necessary for most steering and suspension repairs (which I seem to have a lot of lately).

Carrying a larger selection of sockets and wrenches can be useful if you have to work on other people's rigs. There is a lot of "close enough" overlap between metric and SAE (ex. 13mm = 1/2", 19mm = 3/4", etc) so I just carry a set of metric sockets and wrenches. I also carry a set of torx bits because a friend has a Jeep. One thing I haven't seen in some tool kits is a spark plug socket, which can be useful if you need to tighten/check/clean the plugs or blow oil out of the cylinders after a roll over.

https://www.overlandbound.com/forums/threads/vehicle-inventory.10765/

I have seen a whole lot of scrambling and searching through everybody's rig in an effort to find the tools/pieces to put another rig back into operable order.

I carry my stuff with the expectation that I will likely end up using it on someone else's rig.  And I don't know which size tools their rig will need.[/QUOTE]

Certainly, I've used my tools on multiple occasions either by loaning them to someone or wrenching it myself.   My 1/2 breaker bar, and sockets have come in handy for that sort of thing more than once. Bringing an entire tool kit, or even half of the tools I have on hand, would simply weigh too much and take up valuable space. It is only my opinion though and it works very well for us.  Perhaps it depends on distances traveled.  If I were going on a somewhat local run with a group, then sure, I'd pack in an extra this or that,  including tools like chainsaws.