Just sell them on the cheap, why waste the money, the real good domain names are already in the hands of the speculators. What is left over aren't any good ones any more.
Usually the smart thing to do is check which bring revenue and sell or let expire the ones that don't ?? Maybe its just me tho...
Unless they have resell value or make enough parking revenue to cover registration costs, then let them expire.
That is what I am thinking to do with most of my domain when renewal time comes around the corner. Or try to sell them for $5 or so to get the invest money back if I am lucky enough otherwise just let it go
every domainer hate renewals... lol renewals happen to me every mth... but its a good sign , we will work harder to get the renewals fee sorted out.. keep pushing urself.
Make a spreadsheet or database with details on each domain, i.e. how much parking revenue, number of visitors a month etc so you can decide which domains are worth renewing.
what you can do is put them for sale if you are not looking to renew them on the next renewal period. what you might need to do is creat a blog/page that includes a list of all the domains and you are trying not to re-new and put them for sale 'make an offer' then you can have this listing on ebay or even put them on sedo. If these domains have been registered for few years then they might have some value since they carry domain age. alot of people will consider that as a value for these domains. Best of luck,
lol, nice Offtopic:- I think you should give me 2 for free, and let me earn money once by selling them ;P