Hey Justin,
One of the rare times a post is exactly what I do! I think I can assist on this one :)
First, let's clarify.
Is it a vineyard (growing grapes to sell/use)?
Is it a winery (creating wine from grapes either to market brands -"labels"- themselves or to sell wine to other wineries)?
Or is it both (growing grapes+using them in the winery)?
There are HUGE differences in evaluating each kind of asset and, although they are in the same supply chain, they are as different in their operations as a general contractor is from an Air BnB host (also in the same supply chain!).
Vineyard valuation models from appraisers are typically a blended market value/discounted cashflow blend, unless the operation is generating boatloads of cashflow above and beyond market value, then they will typically switch to DCF only. That is usually not the case as market value for existing vineyards is typically over-inflated beyond DCF in many markets (it's a "sexy" asset!). Think of this as an agricultural business where you are underwriting new capital costs for improvements (better equipment, staffing, operational changes, etc), yearly input costs (crop insurance, general liability insurance, fertilizers, chemicals, diesel fuel, equipment repairs, electric for water pumps, irrigation repairs, tractor operator labor, vine care labor, harvest labor, etc), and estimating yield (tons/acre) and sale price ($/ton). That last bit is where things get difficult on vineyards and a newbie can get into serious trouble. Yield estimation must be done conservatively and with understanding of how yields affect insurance prices (they correlate directly). The other big "gotcha" on vineyard underwriting is input costs. Many people grossly underestimate the amount of labor that goes into a traditionally operated (non-mechanized) vineyard. It's absurdly large. For example, on our acreage pre-conversion to mechanized pruning when vines our young, our vine care labor costs will swing from $600-800k down to $75-100K after mechanization. Easy to mess up your underwriting estimating labor!
On wineries, things are a bit more straightforward. It is a commercial/retail business with some hard assets (biggest assets by far will be real estate and stainless steel tanks, and maybe any newer specialized machinery though that depreciates very quickly). It will be valued primarily on DCF, with some factoring in of the value of the real estate and stainless tanks (at least they should! an equipment appraisal is wise for tank value, metals are nuts right now).
Feel free to shoot me a DM and we can connect on this sometime. Background on me: we syndicate, develop, and operate a portfolio of large mechanized wine grape vineyards in west Texas and own/operate a custom crush winery (winery which provides bulk wine, fruit processing, winemaking, and wine services to other wineries). I have underwritten dozens of new vineyard developments, existing vineyards, existing wineries, and new winery development. Background before wine industry (and still going strong) in commercial and residential real estate and am, somehow, still a part-time wildlife biologist.