Email marketing companies are a dime a dozen. Just typing the expression into Google is going to throw up a gazillion results, each claiming that it's the one for your company.Yet in this minefield which we call the internet, just how do you really know which is the email marketing company for you? What is it that will tip the scales and potentially create a partner for life?

To answer, you should really be asking the following questions.

What is their core service offering?

A simple start is to question just what it is you'll be taking away from their core service offering. The chances are, your prospective email marketing company will have their own bespoke email marketing management system. Fair enough, but what do you need out of this piece of kit?

Firstly, the software should be user-friendly. One of the best - and most standard - ways of ensuring this is by using a WYSIWYG editor (what you see is what you get). This will graphically reproduce your email so you know exactly how it will look to the receiving user, allowing you to tweak it as necessary.

You'll need a variety of templates, that pull data from whichever resource you currently store your contacts on, and these should be fully customisable to your needs.

Most importantly, you'll need in-depth analysis of your campaigns. Did your recipient open your email? Unsubscribe? Why might they have done so? How many people did it actually reach in the first place?

What is their feedback like?

Check the feedback about the company/software from previous and active users. These are the best people to give you an honest opinion about its usability, compatibility and effectiveness.

Try finding out these things from companies of varying sizes, industries and geographical locations, as then you'll get a decent sample of opinions for many different packaged features.

What is their support like?

Purchasing a piece of software from an email marketing company and then never hearing from them again is the online marketing sales equivalent of robbery.

Your supplier should be contacting you to see if you have any technical issues, or simply to lend a helping hand about making your usage of the software more efficient/more powerful.

You should also expect to receive updated functionality in later versions; possibly extending to social media integration, more reporting tools and so on, should they not come bundled in to start with.

Judging all these things should help you know what an email marketing company should be doing for you, before you hand over your hard-earned cash to them.