I would have to guess that for the half that aren't staying in the cabin or tents overnite, that we can meet at the HQ building in the mornings so you won't have to pay vehicle or entrance fees.

Those in the cabin ($12 a night) have entrance fees included, but you'll need to pay your own vehicle fee ($5) I don't think they charge less for m/c's.  I'll bring a cot and extra linens (just in case), a cooler and a coffee pot.

Being as there will be grill handy , I'll bring a grilling tool and a granny spoon  .   I tend to drink water or Mt.dew i have no need of drinking glass but I'll bet a coffee cup would be good to have. .   If we were to put  some meat on the grill then a mess kit to eat the beans and slaw with might be good.  

I'll bring a back-pack , cot , sleeping bag and tent.   The Savage might not seem so nimble on the way to and fro.  

I have a sleeping bag, got that covered, need to get a mess kit, maybe a tin coffee cup

Verslagen.  Things that maybe you can bring:
Power strip, that might be needed if a lot of people have things they need to charge up.  
Tools.. if you have a reasonably compact set that you don't mind hauling along.  (While I have tools, it is a 2 hour ride to the house and back if someone needs something).
Lighter or some kind of fire stick.

Stating the obvious:
Everyone just needs to remember to bring what you need.   Some things to consider:
Meds, Chargers for phone or whatever, deoderant, comb/brush, other toiletries, towel.  Just think of what you use on a normal day.
And, you can always buy stuff you forget.. or don't want to haul.

I will check out what is available at the convenience store just down the road, (firewood, ice, what else?) and where the nearest real grocery store is to pick up grilling food.
I plan on hanging out on Saturday night for a cookout, story swapping, and mild imbibing of adult beverages.  They throw non campers out at 10pm I think.

Every place I can think of takes plastic, but cash works best for the Biker Bars if you are just getting a beer.. of which there will be a few.    
ATMs are everywhere.. but I never use them, so I don't know if you need to be a "local" to get cash.

Anything else you want me to check on in the area?

Here are the roads actually ridden during the day rides.
The lettered points are explained for each map where appropriate.
Some points just put to adjust the route for good mileage readings.

Saturday http://goo.gl/maps/CX2sZ
B.  Flooded creek crossing.  If those 4x4 big trucks ain't going through, I don't think we should..     Turn around.
C. Sign says road is closed ahead because of high water.  Turn around again.
D. Tower road.  Steep, tight twist, 30mph max kind of road.
E. If you zoom in, you will see Hein road.  That is the way we went.  Google says it doesn't go through to Waring Road, but it does.  You can even see street view all the way through.
First wet crossing that was passable.
F. Alamo Springs Cafe.  LUNCH!!!  
G. Just a gas stop
H - I .  Willow City Loop, and the mad dash back to Harry's.  Barely made it before the hail hit.
J. Getting late, getting dark, trying to rain.  Back to base, and made it dry.    


Sunday http://goo.gl/maps/UWeMN
B. The ranch entrance that looks like a mission.
C. Stone Henge II
D.  The Sisters.  Went clockwise around the loop 337, 335, 41, 336.
E. Frio Canyon Motorcycle Stop and Bent Rim Grill.  Git yer swag and bling here!  
F. Gas stop.   Then the last part of the Sisters on 337 towards Vanderpool
G. Stopped in Medina to eat, they were closed already.  Sent the boys up the Sweet 16 so they could ride over the
H. Hump
and I rode home to San Antonio.

Monday - map 1 http://goo.gl/maps/npoZj
B. Met the group in Comfort and had breakfast tacos
C. Skyline Drive - scenic picture spot
D. The "mansion" Time Ship cryogenic research facility.
E-F.  There's that google glitch again for Hein road.  And this time the crossing was dry.
G. There be buffalo here!!
H. The booming megapolis of Kendalia.  General Store and Post Office.
I. Gas stop.. Versy was on reserve.
J. U R Lost.. really.. it says so.
K. The very pretty scenic stop.  
L. Middle Creek "where did the road go?" creek bed crossing.
N. BBQ at Miss Mae's  yummers.  
P. Ran out of google map points.  On to

Map 2  http://goo.gl/maps/9rpSA
B. Devil's Backbone.  Really.. it' just a few twisties, but fun.
C. Shade Tree Saloon and Grill.  Very much a biker hangout.  And where I said "adios amigos" to the gang.  
Sent them on their way west on 473, and I went home along some back roads.