I maybe after another one soon, I got another one in feb this year and not full just yet.
I said 5k as I think thats about right, the van 3k (I could be out on that as not searched for the model for correct price on its own, and a second hand wfp system 2k I think is about fair as you can buy systems way under this new now, I understand it is hot system so maybe another 500/1000 if it is an onboard ro system.
it maybe worth the guy seperating and selling seperate if hes looking for top money.
I think my estimate is a fair one