Had a thought yesterday. Do you think it'd be viable to buy a dehumidifer and hire it out to customers after the jobs finished? Obviously not all would want it but k get so many people asking how soon they can paint it and can they get the heating in to dry it out. I always advise customers to leave the heating off until it's fully dry. But a dehumidifier just takes the moisture out of the air so shouldn't affect the plaster?