Allright. You do not need any special access points to accomplish this. You can continue to use the 105 APs that you have right now. Here is what you need:
1. ArubaOS 5.x or greater
2. Control-Plane-Security Enabled and Auto Cert provisoning turned on (Configuration>Network > Controller > System Settings>Control Plane Security). WARNING: If you do not have this turned on in a production network, but you decide to , it will cause an approx. 8 minute outage until all your access points get certificates.
3. Run the WLAN/LAN Wizard and create a new group that will house the APs at those remote sites. Make sure you create a Wlan of the same name as your internal, except that the forwarding mode is bridged. Put a VLAN-id of 1.
4. When you are finished creating that new group and WLAN go to that new group and add the Virtual APs of the visitor and contractor wlans to it (configuration> Wireless> AP Configuration> Edit New AP Group. Expand Wireless Lan, Click on Virtual AP and in the dropdown to the right, find your contractor and guest WLANs and add them to that ap group
5. Provision new APs to that group and test.