OK, not really.
D&D has (at least) 3 overlapping types of stuff your character carries:
– Equipment, items which permanently shape the character and which you would definitely include in your PC’s portrait. At the beginning of the game this is purely shaped by the player, but over time the DM, via treasure, influences this. 4E’s treasure lists encouraged letting the PC suggest/request gear in part because Equipment so firmly shapes a PCs capabilities.
– Tokens, items which conditionally and briefly act like Equipment, but then are gone. Potions and scrolls fill this niche, but so do things like keys and context-sensitive tools like rope, flasks of oil, or belladonna. Even the humble iron ration fits here — it’s a potion of long resting outside of town.
– Loot, placed and described by the DM; coins and trade goods and such. More valuable than directly useful. This can overlap with Equipment, but the main point of Loot is to get it back into town and turn it into Equipment and Tokens.
Shopping for Equipment and Loot is (almost always) interesting. Questing for a new piece of gear or tech or a new spell or whatever is fun, because it’s growing the character in both personal power and depth of characterization.
Loot-shopping is interesting because it lets players revel in their successes and deal with the logistical challenges or plot hooks or whatever the DM threw at them. It’s a chance to explore the setting and show off.
Token shopping, though, is usually not interesting. Of course the PCs refill on iron rations, and maybe they have interesting interactions with the local jerky-maker, but nobody goes on the epic Quest for 10′ of Chain! Or the Legend of the Water-Clock!
Too, it devolves into Guess the Dungeon. I actually really enjoy Guess the Dungeon, don’t get me wrong, but it creates these shopping trips because there’s just so much that could happen, and each individual token to defeat each individual challenge is so cheap and light.
PCs — smart PCs — wind up with equipment lists containing 5lbs of a hundred different feather light tricks and traps: twine, fish-hooks, pins, chalk, candles, bells, vinegar, garlic, herbs…
So new rule about items, specifically to encourage NOT shopping for uninteresting tokens.
Some tokens are tracked explicitly, in particular, those looted from a dungeon or those that are reasonably rare (scrolls of high level spells, rare potions, specific keys…). You track them as today — cost, location on body, encumbrance, etc.
For everything else (cheapish mundane gear, cheap magical gear, torches, rations…), you can buy an Adventurer’s Kit.
Decide on a weight and a value of Adventuring Kit your character is carrying. You may freely choose these values.
Write Adventurer’s Kit on your character sheet; cost equal to value; encumbrance equal to weight + 5lbs (base weight made up by never-on-screen boring supplies like backpacks, tents, cooking supplies, water, etc).
You may, outside of combat, rummage around inside the kit to recover gear appropriate to the situation at hand. You must expend weight and cost as you do so; you may not attempt to retrieve any item from the kit which wouldn’t fit under the kit’s remaining weight and value.
Each class of item below has a probability of being in the kit. If the roll is passed, the item costs however much it would normally cost. If the roll is failed, the item costs 10x as much as usual (round up to 1gp), but is still produced if the kit has sufficient value. Else, no dice: you didn’t pack it.
You can hang on to a given piece of kit for as long as makes sense. This is usually about 6 hours (“until a long rest”); items in the <1sp are probably just one scene (“until a short rest”); nonconsumables in the 100gp bucket are probably replacing lost or broken equipment.
– Camping Gear: 1+ on a d6. Rations + tent, bedroll, cooking supplies, firewood, etc. When your bag is out of value but still has weight, it's filled with firewood. Remember: rations cost 0.5 gp & 1lb per day; they're just boring to track and roll for each day.
– Cost <1sp: 3+ on d6. Incidentals and things a peasant might own. Examples include a torch, a jug, chalk, a candle, 1 pint ale; 1lb flour.
– Cost <1gp: 4+ on d6. Small & simple objects, farm-house substances. Examples include a fishhook, a needle, a small hammer, an inkpen, a lamp, 1 pint oil, 1 pint wine, paper, a spike, a 10' pole, a sack, soap; 1lb pipe-weed, 1lb iron.
– Cost <10gp: 5+ on d6. Tools, glassware, industrial substances. Examples include a bell, 5 darts, 20 arrows, a javelin, a dagger, caltrops, a scroll case, a crowbar, a shovel, a vial or bottle, a sledge, sealing wax, 50' hemp rope, a lantern, a vial of ink, a matchstick, a grappling hook, a musical instrument, common outfits, holy symbol; 1 lb spices, 1lb silver; 1 gallon wine.
– Cost <100gp: 6+ on d6. Specialized tools, large metal objects, alchemical objects. Examples include hand-weapons, 10' chain, simple lock, manacles, small steel mirror, 50' silk rope, healing potion, flask of acid, alchemist's fire, antitoxin, holy water etc, thief's tools, climbing gear, 1st-level spell scrolls, etc.
I'd probably allow specialized kits — alchemist's kit for instance, containing fluids on a 3+ but nothing else. I'd probably modify costs based on surroundings, for instance in a desert, rations might roll at -1 or worse.
And within a session, to prevent cheese, you'd probably want to remember what was/wasn't in the kit. Similarly, you might charge a kit "broken glass damage" equal to falling damage. But you'd clear all of this out, and allow players to refill their kits, whenever they hit a place with a store.
The nature of this system is to charge a lot more for normally eternal items (characters don't usually run out of chalk…). Because I tend to handwave prices for time spent in-town, this doesn't bother me too much; you might need to fiddle with treasure a little to compensate.
On the other hand, you could give intelligent creature's lairs a value in Kit which can be assimilated by the PCs, which is a new kind of Loot-as-resource.