I need some help. I have some 30-06 brass that I can't use right now, but I may in the future (years from now). I really have no idea how far to go with this. Do keep in mind that I'm on the coast, humid salt air is a factor. Any help will be much appreciated.
Can anyone advise how best to store my stash of once-fired (factory) brass? Do i need to clean it, oil it...

If there's no point trying to store it for this long I'll sell it. Any idea how much I should ask for? It's 120 of Hornady and 120 of Winchester.

Your big problem with brass is airborne. Acid chemicals and moisture. Excluding both in Zip Loc bags would take care of it. Anything airtight. Military ammo cans also work well. I have brass I fired in highpower competition in the 50's which I didn't even tumble. It was slightly tarnished and stayed that way in Zip Locs. I lived on the Gulf Coast for several years, and on the West Coast for the last 40 and that brass is still as good as ever in those bags. If I was going to store today, I would tumble with a car polish in the media, and put it away the same way. I've used my old '06 and NATO brass many times and it's perfectly fine today. Most of it is dated in the 50's.

10-4 the above comment. I would tumble and either store in Ziploc freezer bags or if you have a vacuum packer you could even seal tighter. Ziploc bags will work great. You might double bag and that will eliminate holes. Oil off your fingers will leave finger prints on the brass so as little handling as possible and you will have shiny brass for years to come.