This paper reports on the results of a test on a Co-operative Software Acquisition (COSA) model in which the users carry out the ICT investment by themselves. The existing models meant to help in the ICT investments process are too heavy and technical to be used in SMEs. A successful ICT investment is an organisational change process in which people have a critical role. The COSA model applies user participation and team-working in the acquisition of Commercial Off-The-Shelf (COTS) software products. The model is designed bearing three objectives in mind: 1) business orientation, 2) agility, and 3) practicality. The model can be applied to ICT investments in SMEs which have a professional team leader with basic business and IT knowledge. The results show that people are willing to commit to the COSA process, but problems exist related to systems thinking, decision making and risk taking.