How should supplier quote comparison be evaluated when buying a rotating clay-pot cooker?

Lock the number of burner positions and each clay pot's heating method, turntable drive and zone control before collecting bids, then issue one technical schedule for every supplier to complete: turntable speed and indexing accuracy, per-pot flame or power range, ignition and flame-failure protection, rice-crust temperature profile, exhaust connection, and a consumable spare-parts list. Real differences appear during continuous peak service, when turntable stalling, slow heat recovery and falling crust quality expose weak designs. A low total often hides a downgraded gearbox, missing zone control or separately priced spares, so compare three-year parts and energy costs and request trial records from a similar outlet.