If you get a nutplate jig for a number 6 screw that does both double and single wing nut plates, you won’t need any others for an RV build.
Just start with a #28 drill bit for a number 6 screw, drill the lug holes and then drill out the center hole to the correct size for your screw, since the nutplates have the same wing dimension in most cases.
VANs uses almost all #8 nut plates, except for a few larger ones, but you may want to use smaller #6 screws in some places.
Mini nutplates and larger nut plates, like some 1/4” nut plates, are different but for those few you can use the nit plate itself as the jig. A little slower but there aren’t that many in an RV build.
For an example of this type jig, search on the following;
Nut Plate Jig #6 Single Wing Standard 518G