A solution that combines crm, project management and a customizable client account?

Question

CRM

Friends, tell me a solution in the form of a crm with custom fields (so that you can add and remove fields that structure information about the client), integration with mail and a form on the site and the client's personal account so that you can correspond and attach documents + api (to implement shared desktop with client). I will be grateful. If someone has developed and implemented something like this, we are ready to discuss cooperation.
Why you need it: we are a consulting company working with employees of customer companies. Accordingly, crm is needed to account for all customers. We interact with clients via chat, send them materials and give recommendations, the implementation of which we check and record the results. Since the information about the client is specific, we need custom fields to reflect this information. And for work - a personal account, in which both the client and the consultant write, with the ability to work together, attach files from both the client and the consultant, and, ideally, the ability to create jointly edited tables and load hotel scripts into the workspace (field collaboration).
It is also necessary to organize interaction between consultants (chat, the ability to delegate clients with the entire history of correspondence, set work tasks and assign responsible persons - something like an outliner with a calendar and the possibility of delegation).
I understand that such a combine hardly exists, but a solution is needed urgently. Therefore, we are looking for several integrable solutions.