We regularly survey prices for server management related tasks. (In fact have a review in progress now.)
We find pricing ranging from as low as $10/mo to as high as $675/mo. The services, expertise and guarantees vary widely. So it is certainly "Buyer Beware" when outsourcing your IT management.
Make sure the services you requests are guaranteed and backed via a written Service Level Agreement. I see many firms that say they do a lot of stuff but nowhere is there a legal document requiring them to deliver it. This is often overlooked.
Hourly rates varied from as low as $19/hr to as high as $500/hr. At the low end, you are mostly getting simple point and click type setup services. At the high end, you are getting emergency support in a niche area, such as DDoS mitigation, emergency MySQL support, etc. In the US, there is the budget camp at $75/hr or less with the next pricing break around $125/hr. The more specialized you get the more expensive it becomes. CTO, advanced DBA, BDR type consulting is typically >$200/hr.
I recommend you think strategically about your IT management partner. Since there is no standard for what constitutes server management, it can be challenging to differentiate service offerings without a lot of effort. This is a key failure in managed services industry.
Also don't be fulled by long list of stuff they do at enrollment. Most of it is standard practice at best and at worst adds no value to your services.
SmartServerManagement gets my vote. They fixed an issue that PlatinumServerManagement wouldn't or couldn't (guessing wouldn't due to what they charge). But then SmartServerManagement do charge slightly more. So I guess you really do get what you pay for.