We did a wishing well for our wedding (we got an awesome lounge suite) and we were gifted between $20 and $1500. The average was between $50 - $80 though. I am a firm believer of gifting what you can afford. Best of luck with your decision.
.... seeing it's *3* of you going & even though he is a relo you aint close to him so i would give between $60-$100, depending on what you can afford & also depending on if it's a lavish reception or something simple IYKWIM !!
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