In return she would have a single room with private bathroom, internet, cleaning, washing and household expenses covered. Also breakfast. No lunch or dinner. Your own key. And free morning until noon (approximately 3 pm) and weekends. That time would speak in Spanish and she could spend on whatever she wanted.
House rules: Respect hours of "work" and rest. Can receive visitors in her time / days but those visits may not stay overnight at home.
I live in a large apartment with pool in good area of Malaga.
During her free time she can have a job, teaching children, care for them. You can use the house and I do not get the benefit of that