QDEAR BARRY: The house I'm buying has an old shingle roof. It shows no signs of leakage, but my home inspector said it could need replacement in about three years. Is this a good reason to force the owners to replace the roof? If not, can I withdraw my offer to buy the property? -- Emanuel

ADEAR EMANUEL: After a home inspection, buyers typically ask sellers to make repairs. But such exchanges are matters of negotiation, not a redress of grievances. This means that you can ask, you can cajole and you can wax eloquent. You can use well-intended smiles and a politely stated "pretty please." Or you can hold a pair of deuces close to your chest and bluff. But in most cases, you cannot force sellers to perform.

Standard procedure is to submit a formal wish list to the sellers and then bargain as vigorously as you are inclined. But you cannot require that sellers perform contrary to their specified obligations under the purchase contract. If the contract stipulates that roof defects must be addressed before closing escrow, then you might have a legal basis for demanding roof replacement. Otherwise, you can merely ask. If the sellers refuse, you can cancel the contract or buy the home as-is. Most purchase contracts are contingent upon the buyer's acceptance of the home inspector's findings. If a roof with a three-year life expectancy is not acceptable to you, then canceling the transaction is a contractual option.

In most cases, a roof with three remaining years of serviceability does not warrant canceling a purchase, but every situation has its own considerations. Given these choices -- negotiate, buy as-is, or cancel -- you need to weigh the value and desirability of the home against the projected long-term and short-term costs.

DEAR BARRY: I'm planning to convert my garage to a small guest unit, with a bathroom and kitchenette. Does this require a building permit? -- Judy

DEAR JUDY: Converting a garage to additional living space definitely requires a permit. According to the model building code, a permit is required if you "construct, enlarge, alter, repair . . . or change the occupancy of a building."

In the case of your garage, you are planning both to "alter" and to "change the occupancy." Additionally, permits are required if you "install . . . any electrical . . . or plumbing system." Building a bathroom and kitchen would thus also require a permit.

In addition, you should determine whether zoning in your neighborhood allows you to convert a garage to a living unit. In some areas, garage conversions aren't allowed. Some homeowners, after spending thousands of dollars on such conversions, have been forced to re-convert their garages.

Barry Stone is a professional home inspector. If you have questions or comments, contact him through his Web site, www.housedetective.com, or send mail to 1776 Jami Lee Ct., Suite 218, San Luis Obispo, Calif. 93401.

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