Without a home inspection, you might as well be buying a house sight-unseen. It may not be required by your lender, but it can alert you to problems - or potential problems - that can help you negotiate some seller payback for repair costs or at least get a lower price on the house.

A home inspector can point out problems in a home, and can be more than worth their fee. We talked to experts who have seen plenty of home inspection problems to look out for, and here are some of their tips for what to check:

Water

In the Pacific Northwest, it's a common problem to find standing water in the crawl space, says Tod Hume, a real estate agent at Windermere Professional Partners in Tacoma, Washington state. "If the moisture has done no damage to the substructure, that is often fixed with a sump pump and some drainage work, usually around $2,000," Hume says.

It's also worthwhile to check for leaks in the plumbing system, water heater and roof, according to Tony Soliz, a senior estimator with 911 Restoration, a home restoration company that specializes in disaster recovery and water damage solutions. The inspections should be free, but repair costs vary by the amount of leaks.

Clogged sewer line

About 20 percent of older sewer lines have root intrusions, says Hume, who recommends hiring someone to run a scope into the sewer line to check for a collapsed line and tree roots. Repair can range from a few hundred dollars to clean out the roots to $15,000 to replace the sewer line.

Dryer venting

This is one problem that South Florida real estate agent Chris Heuwetter says he comes across often, and it's almost never done properly or to code. "There are screens in the exterior termination that collect lint, inefficient roof caps, too much run length of duct, or the dryer is crushing the transition hose behind the dryer," Heuwetter says. "These problems can cause blocking in the venting system and be a very serious fire hazard."

Furnace problems

Even if the furnace is working, there might be maintenance issues that won't be noticed unless a technician inspects it, says Paul Sian, a real estate agent in Cincinnati and Northern Kentucky.

With a recent buyer Sian worked with, the home inspector "discovered severe rusting and degradation of the heat exchanger that could have been a potential safety concern," Sian says. "In fact, when the buyer's home warranty came to look at the furnace they turned it off and told them not to operate it at all until they could have a new one installed."

New furnaces start at $6,000 in his area, he says, depending on how much of the system needs to be replaced.

Electrical problems

Like furnaces and a dryer vent, electrical outlets and breakers can have problems that don't need immediate attention, but are noted often by home inspectors. Either they're not up to the current building code, there are no arc-fault breakers in bedrooms, or current electrical standards weren't required when the home was built, says Tim Hendricks, a real estate broker at Hendricks Real Estate in Texas.

Anti-tip oven: An anti-tip bracket is missing on probably 85 to 90 percent of homes, says Welmoed Sisson, a home inspector at Inspections by Bob. It's an easy, inexpensive fix that prevents the oven from tipping when only a little weight is put upon the open oven door. Oven manufacturers will often send you the device for free.

The anti-tip brackets have been required since 1991, Sisson says, and should have been put in place by the oven installer. If your oven doesn't have one, she recommends asking your oven installer to return and install the anti-tip device for free.

Hiring a good home inspector who will do more than the basics - such as turning on the furnace, air conditioning to ensure that they work and opening the electrical panel - can be the first step to spotting any problems. Unless a home inspection is required by your lender, it may be more cost-effective to not hire one and instead hire a licensed contractor to check everything out.

That can be more expensive than hiring a home inspector, but it could save you more money on the back end.

Brent Vosa, a real estate investor and developer in San Diego who also owns a personal finance website, Vosa, says he has gotten bad advice from a home inspector. Minor foundation repairs would cost $2,000, the inspector told Vosa, but after purchasing it he brought in foundation experts who found $10,000 worth of repairs needed.

"An extra $100 to have the foundation specialists come out during the inspection period would have saved me a ton of money," Vosa says.