Jessica O'Leary considers her apartment in Derry, N.H., a temporary living condition. She didn't even plan to stay the three years she already has.

But that doesn't mean she wants it to look and feel temporary.

"I've made it what it is," O'Leary said. "It could be just a box with white walls and I chose not to do that."

Instead, O'Leary painted the walls in every room, most of in a fresh cream color. She changed the light fixtures. She installed a pot rack in the kitchen. She laid down rugs over the carpets. She even replaced the showerhead in the bathroom.

Some of this, like the light fixtures and the rugs, she can take with her when she moves. But the walls will have to be repainted and she'll probably have a lot of holes in the walls to spackle.

So why do it?

"To me, no matter where I live, whether it's an apartment or a house, it's still my home," O'Leary said. "It's very important to me. I work a lot and when I come home, I want it to be nice. ... I walk in and I like my space. I'm comfortable in my home. I'm relaxed in my home. ... It should feel like a restorative place to be, not depressing because it looks like every other place."

Tim Weeks, a chef from Beverly, feels exactly the same way.

He has lived in many apartments North of Boston and he never hesitates to undertake major renovations at his own expense.

"I've put a lot of time and energy into places and then lost them," he said. But it's worth it, he added, because it's nice to live in a place that feels like your own.

"It's where I spend a lot of time when I'm home," Weeks said. "I want to be in a place that I'm comfortable in."

Weeks genuinely enjoys do-it-yourself home repair and gardening, too. He doesn't want to miss out on these hobbies just because he doesn't own his own house.

At one apartment in Beverly, where he lived for about three years, he said he put about $3,000 into landscaping.

The lawn was overgrown with weeds and neglected, he said, so he dug weeds by hand, pulled out old shrubs, planted new plants and installed a new lawn. The following year, he renovated the backyard, too.

"It took a good 10 to 15 hours a week I would spend doing the gardens out there," he said, "and happily, because I loved doing it."

Weeks also renovated the attic of that house into a guest bedroom, without telling the landlord. He has also ripped out old carpet and redone the flooring if the work didn't seem too difficult.

At the very least, he paints the walls. In his current apartment, where he's lived for two years, he painted the kitchen eggplant and the living room red. He furnished the place with vintage and reupholstered furniture, and hung plenty of art on the walls.

"It's just nice to be surrounded by beautiful stuff, and to do it yourself," he said.

Of course, one renter's vision can be another person's nightmare.

Catherine Brown, a rental agent with a 72-apartment complex called Pelham Place in Methuen, said she has seen some crazy decor in her day.

Back when she was renting out apartments in Lawrence, she had a renter who painted a heartbeat line in black, high-gloss paint around the whole apartment. The line ran through the dining room, the bedroom and even over the kitchen cabinets.

Brown was crushed because she hates to penalize a tenant for anything. Fortunately, she didn't have to in this case.

"When we were all in there inspecting the apartment, another resident came in and said, 'My God, I love it,' so it worked out," she said.

Not all landlords would be satisfied with that conclusion. Brown strongly encourages people to check with their landlord, or at least read their lease or rental agreement, before making any changes to an apartment's appearance.

"Stick to the paperwork because a lot of landlords will deduct such picky things from people's security deposits," she said. "I hear horror stories all the time."

Expert advice on personalizing your place

There are many things you can do to personalize an apartment that don't require much time or money. Just check your rental agreement first to make sure you're not jeopardizing your security deposit.

Stained or worn carpets

One of the easiest ways to deal with ugly flooring is to cover it with a rug.

Put down a nonskid pad under the rug to keep it in place, suggests Barbara Reichter of Andover Interior Design.

You can also just get a rug big enough to cover the whole room and let your furniture tack it down, said Tammy Jo Schoppet, founder of the California-based magazine Rental Decorating Digest.

If you don't want to spend the money on a nice Oriental rug, just go to a carpet store, find a remnant the size of your room and have the edges seamed, she said.

Rugs are also good for covering bad linoleum, she said. Or if you're more ambitious and it's OK with the landlord, you can put down peel-and-stick squares of carpet.

Blank white walls

Many landlords allow tenants to paint the walls, as long as they return them to the original color when they leave. That may seem like a lot of effort, though, if you don't plan to live in the space for very long.

You'll achieve a lot with less effort by painting just one accent wall in a bold color, Reichter said.

If your landlord won't let you paint, you can at least ask if you can apply a fresh coat of the existing color, Schoppet said.

If you don't want to paint at all, Reichter said, consider removable wall decals. You can buy everything from small flowers and rubber duckies for a child's room to full-size removable murals and peel-off wallpaper.

Another option is to use fabric as a wall decoration, Reichter said. Hang sheer fabric from a rod to soften a wall or cover cracks and scuff marks. If you use a tension rod against opposing walls, you don't even have to worry about nail holes. You can also use fabric to section off an alcove or to hide an unsightly area, she said.

Schoppet suggests hanging wide strips of fabric or curtain panels in bright colors, such as orange or red, from floor to ceiling with white space in between. Hang the fabric on removable adhesive hooks to avoid using nails, she said.

Or you can try what one creative renter did and put lights on the floor to reflect colored light up on the walls. You get bright colors without the need for paint.

For artwork, use nice frames on posters, Schoppet suggests. Change what's in the frames each season: lighter and brighter colors for spring, warm and cozy colors for winter.

If you must make a hole in the wall to hang something, try using sewing machine needles instead of nails, Schoppet said. They hold up to 20 pounds and leave a much smaller hole.

Covering windows for privacy without a blackout

Catherine Brown, a rental agent with Pelham Place in Methuen, came up with a solution to this problem in her own home in a complex in New Hampshire.

She bought three pieces of decorative wooden fence, attached the pieces with attractive hinges and made an accordion-style screen to go in front of her sliding patio door.

"I got light and privacy," she said. Plus, the fence blocks the cold air, it's a scratching post for her cat and it's a place to hang coats, she said.

Likewise, a store-bought folding screen or Japanese shoji screen can provide privacy without blocking the light, Schoppet said.

You could also consider covering the windows with horizontal wooden blinds rather than mini-blinds or a pull-down shade, Reichter said. You can install them without putting too many new holes in the wall.

One trick for getting more light in the apartment is to hang a mirror opposite the window, Schoppet said. Some people even create a faux window out of mirrors on an interior wall and hang curtains around it.

Everything has to fit into one cluttered room

The real solution to this problem is to simply have less stuff, said Jessica O'Leary, a professional organizer and apartment dweller in Derry, N.H.

"Less is more, for sure," O'Leary said. "Part of being in a rental is you just have to pare down as much as you can."

Look for multipurpose furniture, Schoppet suggests. For example, get an ottoman with storage space inside for office supplies. Ideally, you should try to have everything that looks like clutter tucked away where it's not visible.

Also, put away most of your knickknacks and accessories, she said. Display only a few select items at a time.

If you want to divide up the space, folding screens are a good idea, Reichter said. Try setting one up near the main door to create a little entranceway. A baker's rack facing the door can serve the same purpose, she said. It doesn't block the room from view, but it makes the entrance feel a little separate.

The room is lighted by one dim, old fixture.

Ask your landlord out if you can change the light fixture. Many landlords don't mind, as long as you save the original and make the change safely. And you can take the nice fixture with you when you leave.

"Before you move out, you just change everything back," Schoppet said.

You can do the same thing with the hardware on kitchen cabinets, she added. Just keep the old handles and knobs so you can swap them back.

If changing the light fixtures is too complicated, just set up a lot of table lamps and floor lamps, Schoppet said.

"They're better for atmosphere anyway," she said.

If you want to get creative with lights, Reichter suggests placing some up-lights behind plants to create atmosphere.

All your furniture is mismatched hand-me-downs

Don't hold off on buying good furniture just because you're living in an apartment, Reichter said. You'll waste more money in the long run if you buy cheap furniture that's going to break.

When you buy furniture, buy the absolute minimum number of pieces you need and keep everything on a small scale. Instead of getting a full-size dining room table, buy a small drop-leaf table and a few chairs.

A good goal is to have enough seating in the apartment for six people, she said, including chairs that can be pulled in from other places. Folding chairs are a good way to conserve space, she said.

"There are some really nice folding chairs out there now," she said.

If you're not going to give up your hand-me-downs, use accessories to pull them together, Schoppet said.

For example, if you have two mismatched chairs, find a blanket and a pillow in the same color. Put the blanket on one chair and the pillow on the other. Now find a picture with the same color to put on the wall behind the two chairs.

"It's really easy to pull things together with color," she said.