I thought this paper might be relevant, but at the end - p.401, bottom of the first column - the authors conclude that it might be difficult to measure the QoL of entrepreneurs.
This is available on ResearchGate - it is a large document but see 393-405.
Peters, M., Frehse, J., & Buhalis, D. (2009). The importance of lifestyle entrepreneurship: A conceptual study of the tourism industry. Special Issue-Número Especial Innovación y emprendeduría en el sector turístico Innovation and entrepreneurship in the tourism industry, Vol 7, no.2, 393-405.
I have attached the McGill Quality of Life Questionnaire (MQOL), I have also referenced a study of its validity and reliability. Note: This data tool has been used in various (medical) studies and applied widely across cultures.
Faria, S. O., & Eluf-Neto, J. (2014). Cross-cultural Validation of the Brazilian Portuguese Version of the McGill Quality of Life Questionnaire. Palliat Med Care, 1(3), 7.