Everyone knows that a home's features can make or break a home sale, and that's truer now than ever. But when it comes time to sell your home, not all home-improvement projects are created equal.
While some home improvements  are worth the time and money that you put into them, just as many are not, and it's important to know the difference so that you can show your home in the best light while maximizing your return on investment. 
If you're thinking about selling your house  anytime soon, think twice before making any of these home improvements:
1. Extreme additions
Strategic additions that make better use of home space and lot lines can help at selling time, but home improvements that are too personalized or elaborate may have the opposite effect.
"A lot of times we advise our sellers not to do any major additions to a property, because you could price yourself out of the market, as well as increase property taxes for the future buyer," says Renee Mayhall, RealEstate.com  managing broker for the Carolinas. "You want to sell the home and move on to a property that's going to better suit your needs, and let the buyer put their own personal touch on it instead, because you literally won't get that money back."
2. Enclosed porches and sun rooms
While these spaces hold interest for some, most buyers will see a lost opportunity for valuable outdoor space or a drain on home energy efficiency , thanks to often-leaky glassed-in walls. I've also seen sunrooms on dangerously poor footings, constructed on a thin patio slab. Instead, keep porches well-maintained  and out in the open. An authentic outdoor room is more flexible and appealing to buyers.
3. Way-out wall coverings
Experiments with bold paint colors  and personalized patterns will translate either as far out or out-of-date. Remember, this isn't personal, it's real estate. Keep home interiors neutral so that potential buyers have an appealing canvas on which to draft their own stylistic vision and lifestyle. (Also see "Sell Your Home With These Interior Paint Colors." )
4. Bad basement finishes
Basement finishes can lead to a host of problems for you, as well as for the future owner of your home. Address basement dampness  issues before converting this valuable bonus space, and avoid the temptation to carpet your basement unless you want to start a mold farm.
5. Intricate landscaping
An overabundance of landscape plantings may initially appeal to a buyer's eye, but then they'll start thinking about the time and costs of maintaining a backyard paradise. So simplify your landscape plan  with easy-care plantings that deliver color and impact, and highlight water-wise irrigation systems in your home's listing and open-house tours. (Also see "Landscaping With Low-Maintenance Lawns Saves Money." )
6. Pools and spas
"Some people love Jacuzzis and other spa-like improvements," notes RealEstate.com Atlanta  agent Katrina Walker. "But if it's not a custom home, those may be things you put money into and don't get money back out of when you try to sell the house." Swimming pools also take up valuable backyard living space and add major maintenance and liability issues to a home's real estate profile. Only add one if you plan to be in your home for a very, very long time.
7. Home office remodels.
Though many buyers tend to work from home at least part of the time, a full-blown office remodel can be an obstacle to other uses of valuable square footage. Avoid custom bookcase installations and bulky built-ins that are difficult and expensive to remove or change.
8. Unnecessary improvements.
Replacing a roof when it only needs a few repairs and upgrading plumbing systems are just a few examples of improvements that mean big money that you'll never get back. Instead, stay on top of routine home-maintenance tasks , and let the next owner decide what major improvements to make. Be careful not to let contractors supersize small repair projects by talking you into full-blown replacements.
9. Anything you can't finish
Projects-in-progress shouldn't be among the features of open houses and walk-throughs. If you have a few final improvements in mind, you'll either need to go with a pro or just say no when time and a home sale are of the essence.
"You want to get everything ready before you start to sell, instead of working it out in-between," advises Harrison Tulloss , a ZipRealty agent based in Raleigh, N.C. "If you can do small changes and work with what you've got, it usually ends up working out better than totally re-creating or rearranging, and not getting any value out of the investment."
Tom Kraeutler is a home improvement expert for AOL Real Estate and host of "The Money Pit,"  a nationally syndicated home improvement radio program offering cost effective home improvement tips and ideas .
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