{"slug":"cohabitation","title":"Cohabitation","definition":"Studies of living together, household formation, and the lifetime cost of separate households.","connected_topics":[{"slug":"housing","title":"Housing","href":"https://greyscienx.com/topics/housing"},{"slug":"lifetime-wealth","title":"Lifetime wealth","href":"https://greyscienx.com/topics/lifetime-wealth"},{"slug":"south-africa","title":"South Africa","href":"https://greyscienx.com/topics/south-africa"}],"study_count":2,"studies":[{"id":"GSX:HH-001","slug":"economics-of-living-together","title":"The Economics of Living Together","primary_question":"How do early cohabitation, delayed cohabitation, and separate households compare in a Gauteng lifetime scenario?","summary":"A Gauteng lifetime scenario comparing early cohabitation, delayed cohabitation and separate households.","research_type":"exploratory_simulation","evidence_status":"modelled","series_slug":"household-economics","series_title":"Household Economics","version":"1.0","date_modified":"2026-09-28","links":{"html":"https://greyscienx.com/research/household-economics/economics-of-living-together","markdown":"https://greyscienx.com/research/household-economics/economics-of-living-together/markdown","manuscript":"https://greyscienx.com/api/v1/research/economics-of-living-together/manuscript","json":"https://greyscienx.com/api/v1/research/economics-of-living-together","pdf":"https://greyscienx.com/research/household-economics/greyscienx-economics-of-living-together.pdf"}},{"id":"GSX:HH-002","slug":"the-first-three-years-advantage","title":"The First Three Years Advantage","primary_question":"How can delaying rent and car ownership at the start of a career alter lifetime wealth?","summary":"How delaying rent and car ownership at the start of a career can alter lifetime wealth.","research_type":"exploratory_simulation","evidence_status":"modelled","series_slug":"household-economics","series_title":"Household Economics","version":"1.0","date_modified":"2026-09-28","links":{"html":"https://greyscienx.com/research/household-economics/the-first-three-years-advantage","markdown":"https://greyscienx.com/research/household-economics/the-first-three-years-advantage/markdown","manuscript":"https://greyscienx.com/api/v1/research/the-first-three-years-advantage/manuscript","json":"https://greyscienx.com/api/v1/research/the-first-three-years-advantage","pdf":"https://greyscienx.com/research/household-economics/the-first-three-years-advantage.pdf"}}],"related_questions":["What is the lifetime household comparison between living together and maintaining separate households?","How does the timing of cohabitation change the cost of living and saving?","How does living with parents during the first years of employment compare with paying rent for a separate household?","What is the lifetime wealth comparison between delaying car ownership and buying a car at first employment?"],"claims":[{"id":"GSX:HH-001:C01","claim":"For two Gauteng adults bringing home R30,000 and R20,000 a month, combining households at 25 rather than 35 leaves about R3.972 million more combined household wealth at 75 in the average scenario, in constant 2026 rand. The direct living-cost saving is about R1.059 million. The larger gap comes from investing that earlier saving and from avoiding expensive negative balances.","study_id":"GSX:HH-001","study_title":"The Economics of Living Together","href":"https://greyscienx.com/research/household-economics/economics-of-living-together/claims/C01"},{"id":"GSX:HH-002:C01","claim":"In the central middle-salary Johannesburg scenario, living in the family home and delaying a car purchase for three years creates R602,000 more modelled net capital at age 25, and R3.32 million more modelled wealth at age 60, than moving out and financing a car immediately. The age-60 figure holds when the gap is preserved on the manuscript's common post-25 path.","study_id":"GSX:HH-002","study_title":"The First Three Years Advantage","href":"https://greyscienx.com/research/household-economics/the-first-three-years-advantage/claims/C01"}],"assumptions":[{"id":"GSX:HH-001:A03","name":"Average-case returns and costs","sensitivity":"high","study_id":"GSX:HH-001","href":"https://greyscienx.com/research/household-economics/economics-of-living-together"},{"id":"GSX:HH-002:A07","name":"Common path after age 25","sensitivity":"high","study_id":"GSX:HH-002","href":"https://greyscienx.com/research/household-economics/the-first-three-years-advantage"},{"id":"GSX:HH-002:A04","name":"Contribution while living at home","sensitivity":"high","study_id":"GSX:HH-002","href":"https://greyscienx.com/research/household-economics/the-first-three-years-advantage"},{"id":"GSX:HH-002:A06","name":"Hybrid transport while the car is delayed","sensitivity":"high","study_id":"GSX:HH-002","href":"https://greyscienx.com/research/household-economics/the-first-three-years-advantage"},{"id":"GSX:HH-002:A03","name":"Johannesburg housing bundle","sensitivity":"high","study_id":"GSX:HH-002","href":"https://greyscienx.com/research/household-economics/the-first-three-years-advantage"},{"id":"GSX:HH-002:A02","name":"Middle starting salary","sensitivity":"high","study_id":"GSX:HH-002","href":"https://greyscienx.com/research/household-economics/the-first-three-years-advantage"},{"id":"GSX:HH-002:A01","name":"Representative worker","sensitivity":"high","study_id":"GSX:HH-002","href":"https://greyscienx.com/research/household-economics/the-first-three-years-advantage"},{"id":"GSX:HH-001:A04","name":"Surplus is invested","sensitivity":"high","study_id":"GSX:HH-001","href":"https://greyscienx.com/research/household-economics/economics-of-living-together"}],"datasets":[{"id":"D01","title":"The Economics of Living Together","study_id":"GSX:HH-001","href":"https://greyscienx.com/research/household-economics/economics-of-living-together/data"},{"id":"D01","title":"The First Three Years Advantage","study_id":"GSX:HH-002","href":"https://greyscienx.com/research/household-economics/the-first-three-years-advantage/data"}],"links":{"html":"https://greyscienx.com/topics/cohabitation","json":"https://greyscienx.com/api/v1/topics/cohabitation"}}