Hello,
You could do DHCP reservations so that the AP's always get the same IP address but they still do it dynamically so no additional configuration is needed at the remote end?
If your issue is just AP's picking up a different address if they lose thier lease, DHCP reservation will fix that for you.
You'll just need the MAC address of the AP which I'm sure that you can find on the controller.
Are you just using a DHCP service from a Windows server?
Are you using DHCP or DNS to help the AP's find thier controller or are they all on the same subnet?
Thanks
Ian