The main difference between a wireless and wired alarm system is the cost of maintainence. It is generally beneficial for to go with a wired option, as the cost of maintaining a wireless system will generally outweigh the upfront cost of having a wired system. This is why at Access Alarms we will try to use wired options whenever possible. The only scenario where we may suggest a wireless system, is if it is covering a very large area, such as a large warehouse.
In all of our wireless devices we will use a CR123A Lithium battery, which will generally last about eighteen months to three years. This is one of the biggest disadvantages to using a wireless system. When the batteries do eventually run out, it may be at a very inconvenient time. It is not pleasant to hear a constant low-battery beeping at 2am, when you are trying to sleep. The cost of replacing these batteries each time can also add up surprisingly quickly. Each of these batteries cost around $13-$20, and most detectors will use two batteries at a time.
Lets use a system with 5 detector alarm system as an example, as these are fairly common. Every couple of years you will need to replace two batteries in every detector, totally ten batteries each time. This can easily increase your maintenance cost by a few hundred dollars every two years.
The initial cost of installing a wired system may be a little higher than a wireless system, but it will save you money for the years to come.