Hi Chris, thank you for joining the topic!
Email campaigns can be a great way to get your details in front of people as you can pack quite a bit of info into the one email.
The main disadvantage here is that you will only be able to gather a generic email address for the majority of commercial prospects as they don't tend to advertise decision maker's email addresses! Email to the generic addresses will usually end up going to a receptionist - hopefully they will forward this onto the decision maker, but you also risk it going straight into the trash file - at least this was cheaper than posting a leaflet and it going in the bin!
The best way to approach an email campaign is to carry out some research over the phone before hand - if you call these companies and speak to the receptionist there is a good chance of getting an email address for either the decision maker, or second best for the correct department for your service.
Now the info you are sending will go to the correct person/department and be relevant. If they are interested and have a need they will hopefully get back to you. An alternative is to follow up this info through a phone call so that any questions they have can be answered, and hopefully you can convert to a quotation request.
Have you tried email campaigns previously?