Another tact is to post the stollen bass on craigslist offering a reward. You don't have to say what the reward is. It will do two things - one, it may prevent someone selling it on craigslist so they won't be able to 'unload' it. You won't get it back, but they won't have that platform to sell it on. And two, if someone responds - you may get it back. If this happens, just be sure to be safe about a possible retrieval. As in, meet in a public place like a coffee-shop (
not at a location they choose, like a parking lot etc) and offer only what you feel justified to afford to get it back. If they aren't willing to do that, then end the communication. But, if the person agrees to meet at your choice of location, and it's your bass and you are ready to pay whatever to get it back - just make the transaction and don't ask any questions. There will be no way of knowing if the person you are dealing with is the one who stole it so considering having police there is probably not a good idea because it would be too hard to prove.
I had one of my custom gilded bodies stollen from my front porch by a "porch pirate". It was delivered by FedEx from Pat Wilkins who did the final finish on it. It was insured for over $500 and should never have been left on my porch. I'm currently dealing with FedEx attempting to get to the bottom of it and FTR, they are doing everything they can to not take responsibility for it.
Anyway - here's the link to my craigslist ad to illustrate how you could list your bass.
STOLEN - musical instruments - by owner - sale The $123,456 is to grab someones attention and does not mean that obviously 'mock' amount relates to "the reward" or anything else for that matter.