SDL GroupShar, TM and NMT, how to?

Hello All
I hope that I posted this Q in the right place.!
I'm working in Translation Office
Language Pair: Arabic ---> English
Domain: Legal
Number of Translators: 5

we are looking for :
  1- Adaptive, Neural MT Legal (Ar<->EN), I know that this  service is not available in SDL, but I ask for other providers and how to connect with SDL Trados translation system
  2- Collaborative translation, I need more information about SDL GroupShare ( Price, Number of concurrent Translators) and how users access to servers.
  3- Which is the Best version Of Trados studio suitable for our office.
 4- how to connect to third parties (Neural Machine Translation, Adaptive) and share it in our Translation System Based on SDL Trados Studio?

5- any suggestions, advice are extremely welcomed from you
Thanks in Advance