OK, so let's go with system design/features so.
Notifications you'll get via a communicator, often called a 'digi' in the business. They generally come in 3 varieties. Ones that use a phone line, a GSM (which you'll need a SIM for), or radio transmitters.
The first two are cheap, and can be configured to contact you or a number of pre-set numbers with a pre-recorded message which can be detailed enough to even state what alarm zone has been activated, depending on the alarm system.
A determined burglar can cut a phone line, or use an easily obtainable cell phone jammer to render these inoperable. To combat that, you could sign-up to a monitoring service that poll your alarm on a frequent basis, and will raise an alarm if they fail to make contact.
The other option, the radio transmitters will mean you need to sign-up to a monitoring contract with a provider who supports radio transmitters. It's near impossible for someone to jam radio transmitters with easily obtainable/portable equipment. Radio transmitters are more expensive than the phone line or GSM communicators.
Alarm systems.
Alarm systems come in three varieties, wired, wireless, or hybrid. As your house is pre-wired (the builders or whoever have run wires from a central location in the house to all windows, external doors, etc.), you could go with a cheaper wired alarm, the sensors are much cheaper, and there's no messing with replacing batteries every few years. Fully wireless only makes sense where fitted to houses that are no pre-wired.
Best of both worlds is a hybrid panel, this will support a number of wired and wireless zones. The panel is a little more expensive, but it gives you flexibility to extend the alarm at a future point without having to run cable, or to include outbuildings wirelessly where running a cable would be impractical. This is what I went for in my own place where I've a workshop ~30 feet from the house covered.
On to system design.
An active bell box on the front of the house is a must, one that has active flashing lights to indicate it's not just a dummy box. I've been told by Gardai that this is very effective. If you're covering outbuildings, no harm putting an additional bell box on these to make it clear they are alarmed.
Ideally, you want sensors on every door and window. Perhaps motion sensors inside too. For windows, you might want to consider impact sensors that can detect someone breaking the window rather than limiting yourself to sensors that just detect whether the window is open or closed.
If it's two storey, you may want to be able to arm the downstairs entry points/windows at night. Perhaps a second keypad upstairs then to arm/disarm if the proposed downstairs keypad isn't convenient for doing that.
You may also incorporate motion sensors in key points to catch anyone that has managed to evade the perimeter protection. Usually a good idea to cover hallways.
Another point worth making is that since the introduction of the Private Security Act, it is illegal to employ someone to provide a security service who has not been [broken link removed]. You can be fined up to €3000, jailed for up to 12 months for doing so.
That should give you something to think about for now, come back if you have any other questions.
Leo