A specific business method, an electronic unit and software system for trade intermediation, when an effective tool on real estate market is trading with warranted real estate transaction services, time-limited conditional option commission blank form and extra parte mediation reward. Such a business method could be supported by network, reference or direct marketing. Insurance like business—the profit is gained from unrealized transactions, but for unconsumed services money back guarantee at nominal price level could be granted by using multilevel price marketing.