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Sure, that's why I asked you to describe what the "problem" you want to address is. Free stuff isn't a problem for recipients. Some providers consider it a problem, but IMO it's usually a different problem than they think.
The cab driver may be sad that they didn't get revenue from the second rider, and consider that to be a big problem. Your housemates may not consider old paint a problem, and almost certainly don't consider free paint to be a problem. You or your housemates may or may not consider jealousy or bad feelings about "fairness" to be problems.
See also: kickstarter - everyone pledges what they want, nobody pays unless the funding minimum is met.
For your side of the painting problem (you want new paint, and suspect your housemates do too, but you're not willing to pay for the whole thing), auction design can likely work. If you demand equality, it's easy - everyone agrees to pay their share or the painting doesn't happen. If you don't, then everyone secretly writes down the amount they're willing to pay, and if the pot covers the painting, do it. Any extra gets refunded proportionally (or spent on better paint).
I guess it's worth mentioning one common "solution": extortion/taxation. Threaten to punish people who don't pay what you think they owe. Usually combined with opacity and not telling anyone exactly how their payments are spent.