I'm coming to the conclusion that it would be better for me to do this, rather than ending up with a load of half completed sites. Of course I get the odd purchase enquiry, and then I have to decide if I want to abandon the "work in progress".
Thanks for all the replies. The sensible move would seem to be to list everything until you get round to some serious development. " make offer " for most of them, and BIN for names that you want to flip.
Generally trying to speculate years ahead. Everything of course is always for sale but my target audience isn't on a new name. Just like if a name is expiring it may sell with over a year to go but with a couple of months to go buyers will await your decision to renew.
I usually do list a BIN price. Normally my first cycle price will be a reasonable price I hope to get, and if no nibbles after a bit of time I reduce it (and then reduce a lot if it approaches expiry and I don't plan to renew)..