DON'T base a business on drop-shipping. Drop-shipping means you are not in control of what is shipped or when. DON'T buy mailing list unless you know what they are. Others may be opportunity seekers who may have asked about something entirely different from what you offer or the names may be old. The average American moves every five years.
Some mailing lists out there are in excess of five years old.
Know who you but your lists from and how many of your competitors use the same list for similar offers. DON'T rely totally on mailers for your business. Use mailers when it suits your purpose but be aware of how they work. That's up to 31 pages of competition, even if your mailer is totally honest and doesn't include competing offers in the same envelopes. Bulk mail is neither forwarded nor returned to the sender when undeliverable.