The first chamber of commerce to approach you is probably going to be your local city chapter if one exists. For us this was the Greater Vancouver Chamber of Commerce and they didn't approach us, we sought them out. Why? Because we're new small business owners and we figured that's what you did, you united with other business owners in your area to talk business, maybe in a nice lounge somewhere--I dunno because our reasons from the get go were pretty unclear.
Finding them was impressively easy as they own one of the most clearly choice domain names ever.
A polite, well dressed, rep dropped by a fat folder full of facts. The folder explained that there were numerous advantages to joining: networking, organized events, press, advocacy, discount programs, and more.
The Labor and Industries (L&I) information they offer to sell you as part of your joining package is freely available from L&I, whether it saves you any money or not is very dependent on your type and stage of business. The Chamber has no legal authority or governmental authority, and they meet at 7:30 in the morning and if you want a ribbon cutting--well son, you pay for it. It's not like the Mayor suddenly notices that a new and shiny small business has gone to epic lengths to rehab a portion of the City and decides he should take a day away from his golf game to come pat you on the head for your troubles.
We didn't, our esthetician went to a complimentary GVCC meeting and handed out cards for free services to 50+ members and won a door prize for a second complimentary event where she did the same again. I mentioned earlier that we always look for measurable ROI in our would be partners, we saw less than a 1% redemption rate for our vouchers. For us this meant, whatever other advantages there were to joining, we probably weren't going to get a lot of new direct customers here.
Couldn't tell you as we didn't join so your YMMV but I think as a new business owner you would be wise to avoid monthly fees until such time as income--and more specifically income after expenses--is fairly regular. Having a group show up to smile at your shop and cut a ribbon isn't going to magically put your business in the black and when you're considering the advantage of gaining access to a new group of people you should realize that only a small percentage of that group is likely to do anything but ignore your business.
It's called a vote, every citizen gets one. Everything beyond that is a layer of cruft over a clean and simple process. Our feelings are that buying a business license from the City should entitle us to free membership in our local chamber of commerce but really that's just the point, the GVCC is a for-profit organization that is free to do business any way they like and they like to receive monthly payments so that they can afford to send representatives to City events which thereby builds their reputation and attracts more businesses. There's a fine line between advocacy and marketing and for us and our Spa, we felt like they were more about marketing and self-promotion than advocacy.
It's just what one small business did. In all our dealings with them, the GVCC never did the one thing we would expect from a Chamber of Commerce, they never asked us, "How can we help you?" they only advertised their list of features. This is something we see repeatedly with marketers, they are eager to talk about themselves and their features, and they are slow to look at your business specifics and examine your POV. Good advocacy, heck even good marketing, is a job for good listeners.