ReadyAPI TestFor REST, SOAP and other popular API and IoT protocols, SoapUI NG Pro provides the industry's most comprehensive and easy-to-learn functional testing capabilities. Based on open core technology proven by millions of community members, SoapUI NG Pro helps you ensure that your APIs perform as intended, meet your business requirements, timeframes, and team skill sets right from day one.
The cost is not that bad.
I think the number of users is also limited, considering how much we pay.