I have mine on CL as well and when I get responses like you allude I know it is a scam.
I put in my ad the following words:
"Please reply with "CAMPER" (plus your favorite football team in the subject line to eliminate BOTs and SPAM.) "
If I do not see the above in the subject line (or some will include it in the body text of the reply) then I ignore it totally. So far all inquiries have been serious potential buyers.
Sold the TC, previous owner of 2 NorthStar pop-ups & 2 Northstar Arrows...still have the truck:
2005 Dodge 3500 SRW, Qcab long bed, NV-6500, diesel, 4WD, Helwig, 9000XL,
Nitto 285/70/17 Terra Grapplers, Honda eu3000Is, custom overload spring perch spacers.