Safe Access 420 Classifieds is a State-by-State collection of medical marijuana communities,
featuring free online classified advertisements.

Here are some precautions you can take to ensure that the exchanges stay safe.
First off if you're not using Google Voice already, you should sign up right away. The number you receive will forward to your current number and, if any unwanted callers get a hold of it, you can just block them. It's a really easy way to protect your privacy and still retain the convenience of giving out your number. Of course you can always use a disposable phone too.
Is an email a scam or not? Vague references to your listing are almost always from a scammer. A scammer will just refer to it as "your item" (e.g. "Is your item still available?"). If you get a response that could easily be repurposed as an email to virtually any other listing, delete it outright. Scammers will offer you more than you're asking. Sometimes this will be to cover shipping costs, and sometimes it will be for no reason at all.
Before you meet in person, get the buyer or sellers name. Ask them for a specific form of identification. Do it in the very beginning. They're going to know who you are, so, you  might as well ask them who they are. Any exchanges should always be between legally compliant patients. Please check the laws for your State. 
Also, always have someone come with you. If they drive with you, have them stand a couple of feet away. If something were to happen to you, that other person could run or call for help, and still be far enough away to be safe and deal with it.
Where you meet can make a big difference and the best place might not be where you think. Parking lots are fairly large and you can disappear in a parking lot and not be visible, never within 1000 feet of school grounds. When in doubt, trust your instincts and call off the exchange.
The worst that can happen is that you're wrong, so what? If you're right, you just saved yourself time, energy, money - you name it.
You should keep those safety measures in mind during any circumstance when you're meeting strangers to purchase things from any classified ads.
The important thing for you to remember is never to consent to a search or talk with an officer if you want to preserve your rights. If an officer asks to search you or an area belonging to you or over which you are authorized to control, you should respond:


"I do not consent to a search of my [person, baggage, purse, luggage, vehicle, house, blood, etc.] I do not consent to this contact and do not want to answer any questions. If I am not under arrest, I would like to go now (or be left alone)."

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