Hello, a friend of mine owns a forum in a specific niche of software extensions. He proposed to sell me the 50 000 email addresses from his database. I am developer in this specific niche and I'm seriously considering to maybe run a business and buy this database to advertise for my products. To be more precise, the price of such extensions is around 50$ per year. But first I have a few questions: What are the legal ways to send an email to these people to advertise for my business ? I don't have in mind to spam them, probably just send a single email to present my products and done. How much do you think such a database is worth ? (knowing they are exactly in that niche). Thanks.