I imagine you'd like your IT Support and your IT to be much the same - quick, affordable and reliable. In many cases, you may find yourself faced with having to pick two points of that triangle. And ultimately you'll only know that you're happy with your IT Support once you're onboard with them. Nonetheless, there's a few things you can check to help you begin your search.

Contract/Ad-Hoc flexibility

Most IT service providers will offer monthly contracts which, for a fixed fee give you either unlimited support (remote or on-site, or possibly both), or a fixed amount, after which you pay an ad-hoc rate. In addition, they may offer fully ad-hoc support at a higher rate, but without any contracts.

What you want is flexibility. If a company offers ad-hoc support with no tie-ins and minimal or preferably zero setup/admin fees then that allows you to test the company for yourself. Moving on from that, what about contract lock-in periods? It's understandable that there's a certain administrative overhead for bringing a new client onboard, but does that justify a 3, 6 or even 12 month notice period on a support contract? And surely at the back of your mind you're wondering why they need such lock-ins when your happiness with their service should be the ultimate, and only, lock-in?

Location

In most cases location is important. Although hopefully infrequent, serious issues that bring down your entire network could occur. You need your IT Support on-site to fix, and to do that they need to get there. Whilst you will no doubt have an SLA that determines within what timeframe you can expect a response, the speed at which they actually turn up will be down to a few things, location being one. Workload being another. Their approach to SLAs being another. They may want to get on-site as quickly as possible in order to look good to the client, or they may want to wait a while so the client doesn't feel like they're getting a better response than they're paying for, and then grow to expect it in future.

Trust

Trust obviously is built on the provider consistently delivering over and above your expectations, to the point that you know they aren't going to let you down when you need them. And before you get to that stage? Do you like the people you're speaking to? Do they seem knowledgeable and do they demonstrate that knowledge by showing you how to do things more efficiently, or fixing little issues just to be helpful, that are so trivial as to not come under any SLAs?

Some businesses are under the impression that their IT Support should be 'driving their business forward' but such expectations can be costly. If you expect your IT provider to constantly be proposing hardware/software upgrades then they will, because it will earn them money. Your IT changes should be driven only by the needs of your business, and any suggestions to the contrary by an IT provider should be dismissed.