Shopping for a refinance on an existing farm that is 50%+ paid off and profitable.Licensed cannabis farm is in California.

Either they did not do their homework right (appraisal comes in lower than their estimate, insurance/taxes are higher than their estimate, property did not have clear title, and/or the property has deferred maintenance) or they are shopping without having any experience in the industry. 

If you really want to go down that path, I suggest that you apply to work for a syndicator or RE Private Equity shop as an analyst or operator for a year or two, and browse through 100+ deals over that time period, underwriting each one, and trying to figure out, over that time, which ones you were "right" about, and which ones you were "wrong" about, as best you can.

Someone will lend on the property.I have used 3 different brokers who shopped around for me.

Regarding insurance, i would recommend working with an insurance broker (happy to DM you the one i utilize) and they can shop for the best one for your rental. 

The Short Term Shop operates here and would love to help!

We of course went to a three day work shop.

Box A is direct lender charges, box B are things the lender is making you get that you cannot shop for (for instance, the appraisal or credit report), and box C is closing costs that you can shop/control- Lenders can move things around between boxes A and B to change the way costs appear.

It might be a good time to shop the coverage with several independent agents

You can start to shop for lenders at anytime.