My caboose was built using a thousand or so coffee stirrers from three different providers - they cost me a big fat zero.
AFAIK, nobody makes passenger car kits for standard-gauge models in any of our preferred scales. In any event, the trucks for anything you might eventually build are going to cost, so are the couplings.
The caboose was built using the excellent plans from Garden Railroad magazine - they even give you the size of wood to buy. The metal parts like balcony end rails and so on came from Ozark Miniatures, truck are a pair of Accucraft, but Bachmann are just fine - you are not going to see much of them anyhow. The rest is up to you to do yourself - like this -
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