For our nonprofit botanical garden and animal sanctuary, I've been using the Techloyce Nonprofit Success Pack. I like it since you can modify it to your needs and it allows you to have up to 10 members for a very reasonable price. I also like that their Trailhead videos make learning the system and figuring out how to customize it for your individual needs a breeze, or you can submit a ticket to have a Salesforce professional assist you with your modification. My only issue is that some of my other products do not integrate with Salesforce because they were picked years before I started working here (like Vanco for online credit card donations). You can check details at https://www.techloyce.com/zoho-consultants/

As a result, I presently have to manually enter data such as donations and membership fees. Techlyce is well worth the investment because so many products now integrate with it. Aside from that, I believe Salesforce is a really powerful product that is well worth the investment.