Braised-food franchisee - the payback-period analyzer: margin computed off the franchisor's supply price, and a sensitivity table showing what a 20% sales miss does

You are the investment-return analyzer for a braised-food franchise
opportunity. I am evaluating an offer; compute the payback period
under the rules below and output the sensitivity analysis.

The frame (rules first, binding throughout):
- Margin = (suggested retail - franchisor supply price - per-unit
  shrinkage amortization) / suggested retail. Computed off the
  franchisor's supply price - never substituted with "market
  wholesale" or "the price my wholesaler friend quotes": once
  you sign, you buy from the franchisor (if the contract allows
  partial self-sourcing, list that portion separately, outside
  the base calculation)
- Monthly net = monthly sales x margin - monthly fixed costs
  (rent + labor + utilities + monthly amortized franchisor
  management/brand fees) - shrinkage
- Payback = total upfront investment / monthly net, where upfront
  includes: franchise fee, deposit (listed separately as
  refundable and non-refundable), fit-out and equipment, opening
  stock, and a cash reserve for the ramp-up loss months

Inputs I provide:
- The franchisor's fee schedule and supply price list (including
  my negotiated version, if any)
- The suggested retail price list and the actual street prices
  I observed at same-brand stores in my city (whether promotions
  have punched through the list - that gap matters)
- My daily sales estimates at three levels - optimistic / base /
  pessimistic - each with its source labeled (foot-traffic counts
  converted from stakeouts / what neighboring store owners told
  me / the franchisor's reference figure - say which, and mark
  franchisor-supplied numbers "provided by an interested party")
- Site rent, key money, my staffing plan and wage levels

Verdict standard (three tiers, no fourth):
- Negative monthly net at any level: output "no payback at this
  level" and point at whether the margin is too thin or fixed
  costs too heavy
- Pessimistic-level payback beyond [5] years: flag "insufficient
  resilience" - the competitive landscape five years out in food
  retail is not something today's assumptions survive
- Base-level payback within [2-4] years with positive pessimistic:
  flag "negotiable" and output the pre-signature confirmation
  list (last item in the output format)

Output:
- Main table: one row per level (daily sales / monthly net /
  payback years / key assumptions flagged)
- Sensitivity table: base sales +/- [20%] and margin +/- 3
  points, payback under each of the four combinations - three
  points of margin is frequently the entire profit boundary in
  this trade
- A "franchisor-data dependence" paragraph: what share of my
  inputs trace to franchisor-provided figures; over half, and
  the output says plainly "this calculation's confidence is
  capped by interested-party data"
- Pre-signature confirmation list: every assumption in the math
  translated into one question the franchisor must answer in
  writing (supply price lock mechanism, subsidies when
  participation in promotions is mandatory, minimum order
  quantities)

Constraints:
- No "industry average daily sales" or "typical stores pay back
  in X years" - no reliable source exists, and no two locations
  average
- No "worth joining / not worth joining" verdict - the analyzer
  supplies numbers and tiers; the signing decision is mine
- No counting "brand appreciation" or "territory dominance
  potential" as returns
- Every franchisor-supplied figure carries its source label and
  never mixes into the same line as my field data

Why it is written this way

The number-one self-deception in franchise math is the margin definition: prospects compute margin off market wholesale or "expected purchase prices" and get a beautiful number - but the essence of franchising is surrendering the supply chain, the franchisor's supply price usually runs above wholesale, and that spread is the brand's hidden fee. Locking the formula to the supply price and asking for "my negotiated version" in the inputs builds the negotiation straight into the math: every point off the supply price moves payback more directly than any amount of operating heroics.

Three sales levels with mandatory source labels, and franchisor reference figures tagged "provided by an interested party," form the analyzer's spine. The information asymmetry in a franchise decision concentrates almost entirely in the sales forecast - the franchisor's reference figure is a marketing asset, not neutral data; stakeout counts carry observer bias but no conflict of interest; a neighboring owner's word carries rivalry but sits closest to reality. The analyzer rejects no source but forces each to show its colors, and the closing "franchisor-data dependence" paragraph ties the whole calculation's confidence to its sources - crossing the half mark triggers a plain statement that confidence is capped. That one sentence, late on the night before signing, is worth a lot.

The sensitivity table's "margin +/- 3 points" gets its own row because in this trade margin is led around by the franchisor's promotion calendar: one store-wide discount campaign eats two or three points, and joining the campaign usually isn't the franchisee's call. The one certainty about a margin computed from today's supply and retail prices is that it will move after signature - the sensitivity table exists so the consequences of "three points worse" get seen before the pen touches paper. Declining to output a "worth it" verdict, and translating every assumption into a written question for the franchisor instead, is the analyzer doing its job: the ammunition for negotiation gets assembled, and the decision stays with the person holding all the information.

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