Looking at setting up a on premise IP PBX system at our new hospital and was wondering if anyone here has experience in that field?

Also need some recommendations on a firewall/router solution and PoE switch.  

I recently installed a Netgear GSM4352PB and a Sophos (can't remember the model of the firewall) device. Was quite painless. PBX was an Elastix solution. Was conned into doing it as the guy who knew how to set up the wifi. Will never do it again. Do you have a budget in mind? The PoE switch can vary in cost quite a bit depending on whether you need it managed or not, how many ports you need etc. 

$5k or so between the router/firewall/switch/PBX system. Need a 48 port switch, can't think why I would a managed one. Phone system is going to have 12 extensions. No SIP, using our 3 POTS lines. 

48 port poe switch will eat up half that. Do you need the actual phones as well or just a computer to run the pbx system on?

Everything. I'm thinking of building a computer to run FreePBX and us Sangoma phones.

Having used enough of these phones in the past, it is better to spend a good chunk of change on them. They are all quite poorly made and have a high failure rate. That or budget enough spares over the next year or two. I would going to suggest something open source so you don't have to pay for licenses but the budget I was given was about 3k higher and I didn't know much about this stuff so opted to go the license route so I could get help when needed. 

I was originally set on a Digium Switchvox system until I realized it would require yearly support payments to maintain updates.

What system did you go with? 

You should also take a look at hosted pbx solutions. 

Good luck

Hosted won't work since we have POTS lines and I don't trust the reliability of our internet connection. 

Not sure if you need wireless.  I like the unifi ap stuff.  They have security devices, poe switches and remote management capabilities.  It also allows for guest networks.

Everything is managed and the pricing is good.

Honestly I can't think of any good reason to have an on-prem PBX - just go with Ring Central or something similar.  Yes long-term costs might be higher but not having to manage that shit on your own is worth it.

We are currently in a contract with the POTS lines so AFAIK there isn't any other way.