If you’re using Xero or another CRM, whenever you input the data of a new customer, what you are in effect doing is creating a database. So let’s say you’ve got 500 customers, that’s a potential database of 500 names, addresses, email addresses and phone numbers. Providing you are being GDPR compliant, and all of your customers have opted in to receive marketing material from you, your database for your plumbing and heating business can be extremely lucrative. "if used correctly, a database can add turnover and profit to your plumbing and heating business" GDPR is the General Data Protection Regulation. It’s a legal framework that sets guidelines for the collection and processing of personal information from individuals who live in the European Union (EU). For any business that stores customer data it’s important to familiarise yourself with it. https://gdpr.eu/what-is-gdpr/ If you do have permission to contact customers, then you can use your database for marketing purpos...