'What if we bought a duplex?': Divorced couple buys a home to make life easier for their son. Why purchasing property with an ex can be a smart move

After their split, Lia Romeo and her ex-husband faced the same problem many separating parents do: how to raise a young child across two households without financial strain or constant upheaval (1). Renting two apartments in the same building seemed like a decent solution, but costs were prohibitive. Then Romeo came up with an idea.

"What if we bought a duplex?" said Romeo, recalling the time she came up with the idea in a column she wrote for Business Insider.

The idea immediately seemed to make sense; the mortgage would be lower than two separate rents, her and her ex could build equity, and their son could move between floors rather than neighborhoods. So Romeo and her ex looked around, found an available duplex and made an offer, which was accepted.

Fast forward two years later and the experiment is mostly working out well. "If my son wants to sleep with his stuffed owl or wear his favorite plaid shirt, we don't have to drive across town to retrieve it," she wrote.

Of course, the arrangement isn't perfect — thin ceilings mean a 7 a.m. wake-up on her off days — but the fundamentals seem to be going well.

How Romeo and her ex make it work

The logic behind cohabitation is sound: maintaining two separate households after divorce is expensive, logistically complex and emotionally taxing for children.

Co-owning a property — whether it's a duplex, a shared multi-unit building or even a home where one parent rents from the other — can reduce costs, build equity, preserve stability for the kids and keep coparenting friction low.

Romeo's duplex experiment works because her relationship ended amicably, she and her ex communicate well, and the financial math made sense. But those are not universal conditions for all divorced couples, and making the decision to cohabitate with an ex is not one to take lightly.

Mixing real estate with a former relationship creates financial entanglements that survive the divorce itself, and they have the potential to outlast the goodwill that made the idea seem workable in the first place.

The financial advantages vs. the risks

The advantages of cohabitation can be significant.

Shared mortgage costs and property expenses — like taxes, maintenance and repairs — are split rather than doubled. Meanwhile, both parties build equity instead of paying rent indefinitely, and for parents, keeping children close to both households without shuttling them across town has real value that can make day-to-day life easier.

But the risks are just as real. Co-ownership requires sustained cooperation on financial decisions: who pays what, how repairs are handled, and what happens if one party wants to sell or can no longer afford their share. A breakdown in communication or disparate values could eventually create legal and financial disputes over a shared asset.

There's also the question of what happens when life moves on. New partners, job changes or a shift in financial circumstances can all destabilize a cohabitation arrangement that worked fine when it was initially set up years prior.

Get the legal framework right from the start

If you're considering this path, legal structure matters a lot.