"Free insulation with ISDE subsidy" at the door — scam or real?
Often a scam variant. Real certified installers rarely cold-sell. 5 checks between serious installer and scam.
5 red flags: (1) "We arrange all subsidy for you" + need agreement today — real ISDE is online (rvo.nl), nothing to sign on the doorstep; (2) opaque pricing ("subsidy offset") — demand written quote with VAT, materials, hours; (3) installer not KvK-registered or no liability insurance; (4) pressure for >25% advance or cash; (5) no certification mark (BRL 9501 for heat pumps, RnQ for insulation). Safe approach: get 3 quotes via municipal energy desk or Klantenvertellen reviews. Signed at door: 14-day cooling-off (BW 6:230o) — revoke in writing. Damages after work: BW 7:759 repair right (see also: isolatie-installateur-fout-werk).