I'm about to seek a provider of Emsculpt neo and I was wondering how often can I have this treatment?

It varies from person to person, but you can do it as much as you want every 2-3 days. Some people may reach a plateau, but at the very least you will maintain your results. I would recommend giving it a try to see how you respond and decide for yourself if it's worth it to continue with the treatment.

There is a plateau of fat loss and muscle growth after 4-6 treatments. However, there has not been studied on what more treatments will do to my knowledge. The big key with any of these body contouring treatments is continued diet and exercise to maintain the changes and that in and of itself will continue to promote fat loss and muscle strengthening.

I think you should do once per week for 4 weeks. I will often do include and extra "boost" treatment a month after the initial series then assess results at 2-3 months. I think this brings good results.
If you were looking for something to increasing tone you might consider doing another series or half series 1-2 months after the initial series but that's just my opinion and there is no strong data behind the recommendation. Some providers offer a "medical gym" and allow patients monthly treatments this may allowing continued improvement as well.