I wear costume jewelry, I guess. I prefer "real" materials and avoid resin, base metal, gold-tone/silver-tone, brass, etc. I do have a couple of pieces that have resin, one with gold-tone, but they were beautifully done. I think those pieces were under $100.
I like heavier weight pieces. If they are small, I'll save my money and opt for solid gold - not the hollow cheaper gold. When I need a larger statement piece, I have had good luck so far with silver and gold-over-silver. I would not pay tens of thousands of dollars for a large solid gold piece - it does not get worn as much because it attracts so much attention, it may trend out, etc. Going with a "costume" piece lets me vary my accessories for the cost of a wardrobe piece, and the ones I buy can often be mistaken for solid gold (if people really thought I would wear a big solid gold piece
).
Most of my silver and gold-over-silver pieces run between $50 and $130. I would do rhodium-plated, gold-over-stainless, probably stainless. I avoid gold over brass or "base metal". The gold may rub off one day - that figures into the price for me. I prefer gold-plated to gold-tone because I want the piece to look like real gold, and, in theory, the part that shows IS real gold. The gold-tone often seems too bright or saturated.
For stones, I would do glass, crystal, freshwater pearls, any natural stone, cz, topaz, mop, even wood or shell material if it seems like it would stand up. I think anything that is natural or non-changing and pretty would work for me. I always worry that resin would yellow over time - another reason to avoid it. I don't mind cleaning silver as long as it can be cleaned without ruining the stones on the piece.
I usually buy the costume pieces on sale or at Hautelook, which can be hit or miss. I have had good luck with a couple of gold-over-silver pieces in the $100 range. The $16 pieces (marked down from $125!) I purchased looked like plastic and glue, so I'm not tempted by those anymore.