Most properties will sell in a boom market but some homes take longer to find a buyer than others. For the first-time buyer desperate to get a foot on to the bottom rung of the proverbial ladder, the temptation to buy anything, anywhere, in any condition, is obvious.

But a bargain is only a bargain if it doesn't cost you more in the long run. Thinking of the day you will sell on the day you buy is as basic a concept as bread and butter - but compromise doesn't necessarily mean capitulation.

Some properties are always best avoided, such as those where the title is unclear, leading to endless delays in buying or selling. The existence of a pylon near a house - or an electricity generator - can put some people off. Martin O'Mahony, of O'Mahony Auctioneers, says "Generally speaking, houses on the main roads will have a lesser value. Families don't like them." But railway tracks, flyovers, and road junctions can be a goldmine for some buyers

Some homes seem to be bargains because of where they are, others because of the condition they're in, and some because of both. First-time buyers will want to think hard before pouring money into renovating a house in an area not currently considered "desirable". Yet homeowners who did just that when they bought a house five to 10 years ago in then-not-so-fashionable Stoneybatter have seen their properties rocket in price.

Near-dereliction has its own market. "When you put a house in derelict condition up for sale, people get interested because they think they are getting a bargain and can put their own stamp on it," says Martin O'Mahony.

That was fine when building costs were low. It might take you longer now to repair leaking roofs, and water dripping into a bucket can be enough to end a marriage in the middle of the night. Buyers will have more difficulty getting a building society mortgage for a house in bad condition and in need of major repairs, but the way the money lending market is operating just now means they are likely to get a bank loan - if at a higher interest rate.

"There are bargains to be had with properties that need extensive renovations and if people have access to cheap materials, it can be worth their while," says Peter Quigley of Douglas Newman Good, in Fairview.

On his books at present is 16 West Road, in East Wall, Dublin 3. It is on the market at £85,000-plus, but it requires refurbishment, thus reducing the price by nearly 10 per cent. The gable wall has been re-rendered, there are two bedrooms, two reception rooms, a kitchen and bathroom.

The north inner city is on the verge of renaissance according to the pundits, but prices are still low there in contrast with other inner city areas. On the market through Gunne is 9 First Avenue, off Seville Place, in Dublin 1. It has two bedrooms - but no bathroom, just an outside lavatory and shed. Offers in excess of £65,000, please.

Mary Dillon of Sherry FitzGerald's Templeogue office suggests that buyers on a tight budget should consider buying houses in less than perfect structural order. "The real bargains are houses with cracks. They are the really hard ones to sell but they don't fall down. If a crack has been there for 30 years, it isn't suddenly going to collapse," she says. And you could indeed hold your breath until you have the money to do it up.

A lot of extensions still create problems for building societies but other loan institutions are less exacting. It is a while since Michael Byrne, of Byrne Auctioneers, came across a bath in the kitchen - but it happens.

On his books at present is a house at 5 Clarke's Terrace, off James Walk, in Rialto, Dublin 8. It has two bedrooms, livingroom, kitchen and bathroom but is in very bad repair and the houses next door are boarded up. It is on the market for £55,000. "This is definitely good value," says Michael gallantly.

External factors - like trains, planes, and motorways - bring down the value of a house and make it more affordable. The proposed extension to the M50, for example, has become something of a bete noir. "Some houses in areas where it is planned can cost up to 10 per cent less," says Sherry FitzGerald's Mary Dillon, "though in reality the M50 won't be near residential developments at all."

Buyers are often wary of public dumps, and some people buying homes close to rail lines in places like East Wall tend to hang around timing trains' comings and goings. But then they buy, says Peter Quigley. Halting sites have proved problematic for sellers in the past, although not so much anymore, says Mary Dillon. "We live in more socially enlightened times and buyers can see an established site and see it isn't affecting nearby housing." Look on the bright side if you're looking for a bargain: a flight-path overhead will often reduce the value of a house - but further development in the vicinity of Dublin Airport in north County Dublin is severely restricted. And a shady orientation might suit if you are going to be out of the house all day. In other words, don't be too fussy if you really want that bargain basement home.