System to manage a development / partnerships

[Thomas Ackley]

I have a few developments in the works. Each development has its own entity and partnership structure. 

I am looking for a best practices as it relates to systems used to manage all of this. My partner recommended Invest Next. 

Even though I have good deals in the works, we are still in the beginning phase of a lot of these. The $4000 start up cost seems high and I am not sold on the value the system would bring for the projects. Would Google Drive combined with Slack, Monday or some other project management / communication system suffice for several partnerships with several different entities? Is a system like Invest Next the best practice for structuring and managing partnerships like this? 

https://www.investnext.com/