Maybe I'm the one who scared him off. My comments were pretty harsh.
I do think he paid too much. For example, a 2000 Sun Lite pop-up just came on CL here it the Northwest. The dealer is asking $4400 and would probably take 10-20% off the price.
The Sunlite is a 2000. The camper the OP was considering appears to be mid-80's or so, twice as old. The Sunlite has a 2 way fridge, furnace, gray tank, battery, 12v and 110 electrical systems. The older camper has none of these amenities.
The Sunlite at $4000 seems to me like a vastly superior option to a mid 80's shell at $3000.
https://seattle.craigslist.org/oly/rvd/5994030944.html The Sunlite is ad is pretty representative of campers that come on the market here. It is by no means a loss leader, give a way pricing deal.
Be that as it may, in the future, I shall endeavor to soft pedal my advice to folks, especially newbies, and especially when it conflicts with what they want to hear.
