Our used camper only came with bunk lights.  After taking it out this past summer, I no know that having some fans would be helpful. 

I'm actually in the process of buying 2 unused combo units from a private seller for $50 (shipped).  I guess eTrailer might have been a couple bucks cheaper if I bundled them with enough other items to get free shipping. But overall, this tells me I'm probably paying a fair price.