Easiest junk to collect?

[Nero]

Question is in the title.

[Tempest_Mike]

Perhaps this?

Maybe not, but best I know.

[ghjkl]

Get rich bank

Buy out random item solo

Have it crash

You have junk now

[Levon_]

There is no junk generating method that gives more gp than regular money making. Just own green dragon botters for over 1.5m/h or solo some bosses.

[Troacctid]

If you want to collect junk, that means doing junk trades. Find an item you want that's sold on the street for higher than its GE price, and look for someone who will sell it to you with junk. Buy the item with their junk, and you now have junk to use.

 

The other option is to manipulate prices on the Grand Exchange to buy out an item and artificially raise its price. When it crashes, nobody will buy it on the GE, but you'll be able to use it as junk and sell it anyway. But that's difficult and risky and probably won't work, so you're better off with the first option.