You can set it down, trade it, stick it a secure, whatever you need to do. The only limit is the 3 hour timer from the moment you pick it up.
Anyone can forensics it. Or, you can find the lost items container and turn it in for 1/4 what it would be worth if fully identified and given to the correct person (or 1/2 if just taken to the right city's turn in box)
Anyone can turn it in.
The amount saved is a percentage (purchases from NPCs only) - however, the more saved, the more the virtue progress drops (for example, some people found that while you could save a lot buying the 8 pieces to activate the Kotl City from the guy at the Moonglow Lyceaum (about 150-200k), it would drop the virtue from knight to barely at the follower level.
For me, it took something between 60-80 items fully identified and delivered to go from nothing to knight (two trips about a week apart, in Trammel on a low pop shard). Typically, it takes another 3-10 items to get it back, after a lot of small stuff makes it drop.
The easiest way to gain is to set aside 3-4 hours one day. You'll need a mount (A giant beetle is good for storage of the items found), and a rune book/atlas of the islands of Britannia. You'll want to do this on one facet (though you could conceivably do it on both tram and fel on different days).
You might want to have bags in the beetle to sort by half-hour of searching. You'll not want to search for more than 2 hours at a time, give or take. 90-120 minutes is typical.
- Recall to all the islands. Go around their shores, looking for items on the ground. On the smaller islands, check the interiors. Look for stuff laying out in the open, and pick it up. The better islands appear to be Moonglow, New Magincia, and Buc's Den, though I've found stuff on every island except Ice, though typically not in a guard zone (surprisingly, there's even a couple spots on Skara where items show up, and the north end of the central Jhelom island is often good for a few items).
- Next, recall to outside the Blighted Grove, and go ESE to where the mountains meet the sea. Start there, and follow the shore, and DO A LAP OF THE BRITANNIA COAST, until you hit the other side of that mountain coming up the coast from Skara. Look for items within a screen of the coast (object handles using CTRL-SHIFT is your friend). IF you hit the suggested time limit, remember where you stopped, and head back.
Typically, you can go around the continent, and some of the islands, in 2 hours. Once you get used to it, you might be able to do both 1 & 2 above in 2 hours. This will typically be a haul of 25-50 honesty items, if no one has made such a search in the last week or two, as items tend to not decay (or timer start), unless a server reset harder than a daily maintenance hits. Replacement items seem to be slow, a few every few hours (a trip 2-3 days after my first only found about 20 items, after I had almost 50 the first time).
At the time point, you go back, and forensics the items, starting with the first half-hour's bag (which at this point has items under 60-90 minutes). Forensic Eval items for about 30 minutes (if you have a forensics in the 70s or better, you might be able to do 20-50 items), writing down the items sorted by city, and by NPC name under city (and note the staleness of the item). Deliver items by city or age (you might lose a couple by city if you wait 2 hours to study, but by city is is more efficient overall).
All of the NPCs you will be looking for are Yellow, and are either "Peasant" or "Noble" types (watch out for random NPCs that might have the same name in a different profession). Be aware of just how big Yew and Britain are in terms of farms, and how far out you can find NPCs. You might have a friend scout the cities for you as you're delivering. IF items look to be going to expire because you can't find the specific person, just drop them at the lost and found boxes until you get to items that aren't in immediate danger.
Options:
One of the reasons why the coasts are good, is that if an item's random spawn puts it on water, the server moves it to a nearby shore, within a screen of the shoreline.
IF you or others have already cleaned up the shorelines of the islands and continent, the next best place to check is along the bases of the mountains (as the same thing happens if the item would be underground due to a mountain, popping it to the nearest legal spot). The last resort is to just search cross-country - the Trinsic Jungle from coast to coast, and the woods between Yew, Wrong and Minoc tend to have a few pieces.
In all, while it takes a bit of effort to initially get to knight, maintaining it is actually fairly easy (a few new items every time you see it drop). The last time I raised it up, I collected about 30 items, but only needed 10 to get to knight. The other 20, I gave to a friend, guided them through the cities looking for the owners, and got them half-way from seeker to follower on my leftovers.