Try Dolibarr ERP CRM now. You have 2 solutions :
Solution 1 - A free dedicated instance, only for your, with full admin access : Create in 2 clicks a dedicated clean and secured instance, and start to use it as if it was for a production usage. Instance and data are yours and dedicated to you
You may find other test services, available after registration, provided by several companies on https://partners.dolibarr.org
Solution 2 - Test on the shared instance : Test immediately using the public shared instance of Dolibarr. This instance is not dedicated to you, but used by everyone, and is updated/reinitialized several times a month with last development version (so may not be stable).