While the idea of living with others to save money and generate wealth sounds promising, it would be quite irresponsible for friends or couples to cohabitate together and pay a mortgage collectively without executing a formal written domestic partnership or cohabitation agreement.
While a great way to generate ROI, disposable income resulting from cohabitation will be lost if the parties end up in litigation b/c they failed to document certain rights and responsibilities of the owner-occupants. The best way to avoid cohabitation misunderstandings is if there is a predetermined plan of group ownership with instructions for exiting the partnership and recouping ones equity in the investment upon certain triggers or life events.
Whether clarifying the use of common areas, plans to remodel, the need for multiple fridges/bathrooms or creating a schedule for privacy and parties, the owners investment is best secured from internal liability if their expectations are negotiated and documented in writing well in advance of occupying the property.
I always advise clients to hope for the best but also plan for the worst and, no matter what, put it in writing!✍???