From pulling up the ugly downstairs carpet to painting rooms and installing molding in the kitchen, Aimee Erwin and Joe Shaver have put quite a bit of sweat — and not a small amount of money — into their three-bedroom home.

Yet, by law, the house in Rochester, N.Y., is Shaver's alone. His name is on the deed and mortgage. And the two are not married — not yet, anyway.

That doesn't stop Erwin from doing her share of the work — next up is redoing the upstairs —or deter the couple's mindset that the house belongs to both.

The discussion of what would happen with the house if they broke up is one that the couple would rather not have. "We dance around it a lot," said Erwin, 32.

Shaver, 28, agreed. "We haven't really discussed that. It's certainly a concern we have. But we try to be sort of upfront and honest with each other to avoid that sort of situation."

For married couples, there are plenty of legal protections ensuring that if the union ends through death or divorce, one party isn't left stranded financially. Married couples are presumed to have equitable interest — i.e., equal stakes in the home — as well as equitable responsibility for the mortgage.

But for unmarried couples, straight or gay, it is arduous and tricky to get such protections if domestic bliss sours.

It's an issue facing an increasing number of Americans. During the 1990s, the number of households made up of unmarried couples climbed by 72 percent, according to U.S. census figures.

But it's an issue that rarely comes up in home buying.

"Many people in the gay and lesbian community don't know to ask," said Rochester attorney Jennifer Gravitz, who often consults with gay couples buying homes together. "It really depends on who the couple is, how perceptive their lawyer is."

But it's possible to gain some legal protection and rights through a property agreement — a written contract spelling out how much of the house the two own, buyout rights, how the property tax deductions will be handled, and how improvements or purchases done by one partner will be treated.

Such a contract also can stipulate ownership rights that can become valuable if one member of the couple dies. But unmarried couples buying a house together also should create a will or some other estate-planning device, Gravitz said.

Couples also can opt for a partnership agreement that covers all assets, not just the house, Gravitz said. The expense of having one written up can vary widely, and often can run $1,000 or more.

Erwin said: "Once our finances are in order, we both have wonderful jobs, we get married. It'll be in both our names."