Back of a napkin calculation: showing OP 100 ads of blinds probably costs 0.1$ in the US. The cost of a blind is 100$ (I have no idea, don't live in the US). So

Back of a napkin calculation: showing OP 100 ads of blinds probably costs 0.1$ in the US. The cost of a blind is 100$ (I have no idea, don't live in the US). So if the probability of buying a second blind is at least 0.1% it was worth running the campaign. The fact is, online ads are super cheap.