Both of my units have UV bulbs. If I remember correctly, my air guy charges $125 per unit to replace the bulbs. I think the bulb run around $85 retail. Is there any reason that I should not try to do this myself? the process appears simple to me, but I don't know that this it is.
Just make sure all power to the AHU is turned off, and make sure the UV isn't powered by some other external power supply. Depending on the bulb type, you may want to where a glove to keep the oils from your hand from getting on the new replacement glove.