I've just completed getting a new genset ready to go online.

I purchased a metal .50cal ammo box from Harbor Freight (no affiliation) for $15.00 each. Each box belongs to a genset and has chain & a lock/key, spare spark plug, 1qt of 5w30 synthetic oil, spark plug wrench, genset canvas cover, owner's manual, ignition switch key, wrenches for ea genset's nuts & bolts, electrical plugs & adapters.

The new genset runs on either gas or propane. I will only run propane in it because propane burns cleaner AND after I disconnect the propane tank, I won't have residual gas fumes to deal with while travelling with the genset & propane tank in the back of my truck.