Multiple firewalls or one?

I'm working on taking over management of 5 networks in the same building, each company on a different floor. Currently each company has its own internet connection and a variety of different firewalls/gateways. There are some major cost savings moving to one connection and potentially security improvements to be had.

I've been able to organise for a 1Gb connect into the building but now need to decide how it's are divided.

Option 1 - multiple firewalls Have the internet provider create vlan connections for each network and use their existing firewalls. Each firewall would manage VPNs, security etc

Option 2 - single firewall and seperate vlans Have the internet provider provide one connection going into a new firewall. That firewall would manage all security, VPNs and then a VLAN for each company.

Any views or advice in this situation?