Sue from Michigan made me an occupied sign, and I used it for 2 years, but it was very heavy. I ordered one of those yellow folding boards they use to denote a wet floor. I don't know if this is the exact one, but it looked like this:
https://www.amazon.com/HDFSY-Height-Yel ... afety+signThen, I tried to paint some letters on it, but it looked so bad, I wiped them off and used some stick-on black vinyl letters I got at Michael's. The resulting sign said "Campsite Occupied" on one side and "Be Right Back" on the other. The only problem is that it tends to blow over. If I can push the legs into the dirt, it will be fine. Otherwise, I stick it over my small stool.
Putting a tablecloth on the table also helps. Sometimes people think you have abandoned stuff, so I often tell my neighbors I will be coming and going. Now, some funny stories--once I drove up to the dump station to empty my tanks. A young man came running up (it was at least a quarter mile away) carrying my hose because I had "forgotten" it. He was red-faced and out of breath.
Had same problem with people chasing me down with forgotten items until I started putting my sign out!!
And, Sue, when I was done with the sign, I left it next to the dumpster. It was missing a couple of hours later, so I may see it again some day!
And since the Thousand Trails passes are so expensive, you might want to try out a couple of their campgrounds before you spend the money on one.