It's easy. You need a strain that is better than what everyone else is donating. Average weed is everywhere, if it's dank, they will take it. What you need to do is find out who's in charge like the owner, then give him a few nugs as a sample. To get your foot in the door you might have to go lower on your price at first. If the dispensary likes what you have you'll know it, they will ask when more will be ready. Then all you have to do is give out more samples to other dispensaries till you find someone willing to pay your price. Then all you do is raise your price with the dispensary that took your first donation. If they wont take the price increase then fuck them and move on to someone who will. Also research each dispensary and make sure they don't owe or short other vendors. Go to dispensaries that test meds, that are clean and that care. Vending is a lot of drama so be prepared.