Exact product match is not UK stock proof: a four-case sourcing evidence gate

Disclosure: I build CELL FACTORY. This is an original free offline acceptance fixture, not a verified supplier list or paid customer result.

A listing can match a product photo while failing UK physical stock or single-unit fulfilment. A low item price can also miss VAT, shipping or handling. Treat those as separate evidence requirements; a UKdomain/address is not warehouse proof.

The following Python fixture uses explicit labels rather than treating unknown as false or a supplier claim as independently verified:

"""Original bounded evidence gate; synthetic acceptance fixture, not verification service."""
from decimal import Decimal
FIELDS=('exact_model','uk_physical_stock','single_unit','direct_dispatch')
def assess(row,target='7.00'):
 status={k:row.get(k,'UNKNOWN') for k in FIELDS}
 if any(v not in ('VERIFIED','FALSE','SUPPLIER_CLAIM','UNKNOWN')for v in status.values()):raise ValueError('explicit evidence labels required')
 if any(v=='FALSE' for v in status.values()):return 'REJECT_REQUIREMENT'
 if any(v!='VERIFIED' for v in status.values()):return 'UNCONFIRMED'
 parts=[row.get(k) for k in ('unit_gbp','vat_gbp','shipping_gbp','handling_gbp')]
 if any(x is None for x in parts):return 'COST_UNKNOWN'
 if any(Decimal(x)<0 for x in parts):raise ValueError('negative cost')
 return 'WITHIN_TARGET'if sum(Decimal(x)for x in parts)<=Decimal(target)else'OVER_TARGET'
if __name__=='__main__':
 base={k:'VERIFIED'for k in FIELDS};base.update(unit_gbp='4.00',vat_gbp='0.80',shipping_gbp='1.50',handling_gbp='0.20')
 cases=[base,{**base,'uk_physical_stock':'SUPPLIER_CLAIM'},{**base,'exact_model':'FALSE'},{**base,'shipping_gbp':None}]
 actual=[assess(x)for x in cases];assert actual==['WITHIN_TARGET','UNCONFIRMED','REJECT_REQUIREMENT','COST_UNKNOWN']
 import json
 print(json.dumps({'status':'PASS','cases':actual,'synthetic_only':True,'real_supplier_verified':False,'limits':'Human review assigns evidence labels; code cannot verify a warehouse,model,stock,delivery or payment route. Target is a source requirement, not factory minimum price.'}))

The four synthetic cases passed locally: all checks verified andGBP6.50 total passes aGBP7 target; a warehouse claim staysUNCONFIRMED; a known model mismatch rejects that requirement; missing shipping leaves costUNKNOWN. The target is an example acceptance threshold, not a minimum fee or a promise that a real supplier meets it.

The code does not gather or authenticate evidence. A reviewer must retain dated source references and distinguish supplier claims from independent proof. For an actual sourcing job, add exact SKU/photos, current warehouse/stock evidence, neutral packaging, tracking, minimum order, replenishment, order/payment process and permission for customer delivery data. Direct communications require appropriate authority; do not create orders, buy access or share private customer data just to test a lead.

This small fixture does not validate product safety, commercial viability, a supplier's honesty or future stock. No qualifying supplier or income is claimed. A negative source-backed report is better than passing a similar product as an exact match. What separate evidence gates do you use before calling a sourced product verified?