They are two different things which required two separate development efforts and are subject to two different royalty requirements.
At this time, they are $50 each.
Once you buy and apply the key, any updates/improvements incorporate the improvements at no additional charge.
Upgrades (major new functionality, as were adding support for ProVoice or DMR) are at a cost. I cannot rule in or rule out the possibility that we will offer additional upgrades in the future.