I tried to do some searching to see if Nigeria has any requirements like UL listing or licensing like in the US. It seems like you won't be burdened by too many regulatory issues.
You will likely find that central station management software is much different in core functionality than VMS software. I've known of several central stations that have tried to use Milestone, Avigilon, Genetec and other VMS's as the interface on the central station side with usually suboptimal results. Oddly, Geovision is the company I've most frequently seen used with their own software for monitoring.
Most likely you'll want to invest in SureView's Immix or iViewNow at some point (note: Immix can be used stand-alone, iViewNow requires an automation platform like BOLD Manitou.
These software platforms all handle two key things that VMS's don't:
- Distributing incoming alarms/events to the next/best available operator
- Keep a comprehensive audit trail of when the event came in and what the operator did in case your customer claims you didn't provide the contracted service.
The weak internet connectivity can be a problem, unless you can deploy some kind of private mesh network or metro-wifi, which I would doubt would be practical. Power issues can be handled with a UPS I would think. You will most likely want to monitor systems for continuous availability to be alerted in the event of a connectivity outage. SureView does something like this as part of their "e-care" features.
I've seen a few different pricing models. The easiest one is hourly pricing, like a guard. In most cases companies doing hourly pricing are coming in at about 1/3 the rate of a guard (sometimes higher if they also include the hardware in part of the rate, which usually comes with a 2-4 year minimum contract). You charge $X per hour that the system is "armed", or when the customer would have otherwise had a guard on-site.
Per-camera or per-event pricing is the other main approach. This can be harder to estimate because you don't always know how many events a given site will produce, and customers like predictable billing.
You'll want to find a video analytics platform that is available and supported in your country and specialize with that. Much of your profitability and service quality will revolve around keeping false alarms low so you don't chew up too much time from your operators, while also not missing the key events the customer is paying you to catch. For these reasons it tends to make sense to spend a little more on the analytics if you have to, but most importantly go with something that you feel you can understand and support. Develop a common platform and use that at every site instead of doing AgentVI and Milestone at one site, Avigilon at the next and Axis Defender and Exacq at another.
Also determine if your customers will use the system on their own as a CCTV system, or if the cameras are going to be used/monitored only by your company. If the customer wants access to the system you'll likely need to find a user-friendly VMS that doesn't require a lot of training for users to be comfortable with. You would also likely have a clause that any changes or modifications to configurations MUST go through your tech-support group so that the customer does not inadvertently change something that makes the system ineffective for monitoring.
You can also check http://www.ppvar.org/ for some more information on video monitoring. It is US-centric, but most of the concepts are the same.