Market for Maple Sap

I am exploring the purchase of a farm with a sugar bush in the central and northern areas of Vermont. My plan is find someone to tap the trees and purchase the sap as one of the sources of income of the farm to keep it from being developed. The tap installers and sap purchasers could be the same person or company or not.

Questions:

1. Who installs taps? What is a reasonable cost?

2. Who might purchase the sap? What is a fair price?

PS - I am a lifelong Vermonter who believes that Vermont's agricultural future is bright and that food production & woodlands must be preserved from development.

This is typically done with a sugar bush lease. Check out Vermont's Proctor Maple Research center, Proctor has a suggested lease form, which should be finalized by a lawyer.
I lease 2 sugar bushes and I do all the work, as do most if not all leases. Most leases are based on a per tap lease payment each year and the lease should be for a minimum of 10 years. While a few are shorter, most producers will be unwilling to bear the expense of setting up a sugar bush without at least 10 yrs guaranteed. My leases are 10 yr, and renewable for 10 more as long as I have lived up to the terms. On my larger lease there is also written into the lease, the provision that if the owner dies, or sells the land, that the lease passes to the new owner for the duration of the lease term. I'm not familiar with Vermont's tax structure, but in New York, my landowners qualify for an agricultural assessment based on my production. Here, as long as I average $10,000 in total sales in agricultural products for the previous 2 yrs, they get a nice break in the property taxes.
As an example, on one of my leases (Where I pay $.80/tap/yr the landowner told me his tax savings was greater than the lease payment, but then again, that in in NY, the spend and tax state)
Good luck, you will have no problem finding someone to lease if the site is good for maple production.

By the way, if you set the bush up and collect the sap, there are many producers who will buy good sap, based on the sap sugar %. That could net you more, but would require the investment up front in supplies and labor. It would also require you to educate yourself for proper installation, design and method.
Some producers buy sap outright, on a per gallon basis and most buy it on shares. I buy sap on a 50/50 split. I test the sap for sugar % and calculate how much syrup it will make, I keep half and they get half. Depending on lots of variables, sap may sell for $.25 per gal up to maybe $.50 for sap containing 2% sugar and a split may run anywhere from 30% to the seller up to maybe 60%.
Again, good luck.

Along with what Dave said there are dealers and individuals who will come out and fully set up your woods if you want to go with the selling sap route.