In the good ol’ days, a seller would knock a few grand off the sale price of a home if the inspection found the house had, say, been built atop a Superfund site. Today, if you protest any defects, an owner might decide to put the property back on the market and wait for a more desperate buyer. This scenario leaves house hunters to ponder a difficult question: Which imperfections should you live with (knowing you may have to fix them later) and what flaws should you have the courage to walk away from (no matter how much you love the house)? We asked local home inspectors to weigh in.

Foundation Flaws

Buy It: Vertical cracks in a concrete foundation—which are relatively common because of Colorado’s dry climate and erratic temperatures—are typically no big deal, says Craig Cox, home inspector with Pillar to Post Denver. Most can be repaired permanently for less than $100 each.

Make A Deal: Horizontal cracks, though, need to be examined by a structural engineer and foundation repair expert to assess the damage and potential causes (the likely culprit: freezing and expanding soil). Cox estimates that repairs can range from $2,000 to $40,000, but he adds that even in this market, some sellers are willing to cover the cost or at least split it with the buyer.

Roof Disputes 

Buy It: Asphalt shingles often warp or crumble as UV rays break down their chemical composition. Don’t stress over a few decaying shingles, Chad Chadwick of Seven Stars Home Advisors says. You can often infill sections for less than $300.

Make A Deal: Most asphalt roofs last 10 to 12 years in Colorado. If a roof is older than that, try to negotiate for a roof-replacement credit (approximately $8,000 to $10,000, depending on the size of the house). Based on Chadwick’s experiences, buyers shouldn’t be expected to pay for more than half of the job.

Utility Upgrades

Buy It: If both the furnace and the water heater are less than five years old, consider it a gift from the real estate gods: The average furnace lasts 22 to 30 years, Chadwick says, while water heaters typically hold out for 15 to 17.

Make A Deal: First-time buyers shouldn’t hesitate to ask for a water heater replacement (around $1,500 and up for a regular gas or electric 40- to 50-gallon tanked model, $4,500 and up for tankless). But some sellers aren’t eager to reach a deal on a new furnace. Buyers might have to accept the fact that they’ll have to replace it themselves in the near future.

Plumbing Predicaments

Buy It: Modern plastic sewer pipes are nearly impenetrable. Clay pipes, often found in older houses, aren’t, making them susceptible to intrusion from roots, which can catch paper products and clog the line. However, as long as the pipes are flowing freely (request a video camera inspection to make sure), Cox says, buyers should feel comfortable with a sale.

Make A Deal: If you’re dealing with a bad sewer line, which often requires a fix that could cost north of $10,000, backing out of a sale might be wise. Some sellers, who often don’t know sewer line problems exist, may balk at the repair fees and refuse to fix them. “I’ve seen more transactions fall apart because of bad sewer lines than anything else,” Cox says.