Let's say I see a wallet on the ground and a person I suspect dropped it. In English I would naturally ask" Excuse me. Is this your wallet?" A direct Japanese translation would be"すみませんあなたの財布ですか" but time and time again I hear that using "あなた" is rude. How then do I get around this in case the person a complete stranger?
Ask without あなた (Avoid direct translation).
Japanese expressions will work without the pronoun in one-to-one conversations. If I actually saw a person dropped a wallet, then I would reach the person and say in statement form:
Um, excuse me. [You] dropped [a/your] wallet.
Then again, if I suspect the person dropped a wallet, or if I am not sure who dropped it, then I would reach whomever I saw near by and say in question form:
Um, excuse me. Did [you] drop [a/your] wallet?
No need for the pronoun, use either the statement form or the question form.