However, if you're heading downtown for a day of shopping, it could be cheaper to leave your ride in the hands of a hotel valet.

Close to half of 25 luxury hotels in the Orchard Road and Marina areas charge less than carparks, according to a Straits Times check.

That has some drivers taking a somewhat cheeky approach, leaving their keys with valets and sneaking off to shop.

At the five-star Grand Hyatt Singapore along Scotts Road, valet parking carries a $6 flat fee, compared to $9 for four hours of self-parking before 5pm.

Over at the Four Seasons Hotel along Orchard Boulevard, it costs $10 for valet service. Scoring your own lot for just four hours there would set you back $17.

Another hotel where you could save: the Royal Plaza on Scotts at Scotts Road. There, you could pay $7 to have your car parked and walk five minutes to Shaw Centre to shop all day. Parking for eight hours at the Orchard Road mall before 5pm on a weekday would cost more than double that tally - $16.05.

Valet parking is provided by most of the 25 hotels so guests can avoid the hassle of finding a lot.

But it has emerged as a viable option for drivers who are feeling the pinch at carparks where rates have gone up by between 10 per cent and 20 per cent over the past two years.

The potential of saving money on parking appeals to relationship manager Adeline Lau, 28, who usually blows more than $10 when she parks at the Shaw Centre for eight hours.

But there is a catch, she said. 'I will have to find a way to walk out of the hotel discreetly to shop without being noticed by the valets.'

Some drivers, like one who would only give her name as Ms Ong, are already getting a bigger bang for their buck.

She leaves her Mercedes SLK in the hands of the valet at the Grand Hyatt once a week for about six hours. It sets her back $6, the same as an Urban Redevelopment Authority open-air carpark next to Wheelock Place, but she usually throws in a $4 tip.

She said: 'I'm happy to pay a little more so long as my car is well looked after. In the end, I still pay less than parking somewhere else.'

Tipping is quite normal, said Mr R.K. Vicnesh, director of valet service provider Sakthya Services, which parks cars at the Royal Plaza on Scotts. Most drivers leave the valets about $2 to $3 in tips, he said.

While some hotels know of the potential parking loophole, they are not overly concerned about drivers exploiting the cheaper valet services.

Grand Hyatt's spokesman Patricia Yong said the hotel does not 'discriminate against' the 20 or so patrons who pull up at its driveway every day.

She said: 'We give our patrons the benefit of the doubt. We don't want our genuine customers to feel encroached upon.'

Not all drivers are willing to put their wheels in the hands of valet attendants because of the risk of mishandling or scratching.

As musician and BMW driver Daniel Sassoon, 32, put it: 'I'd rather pay a little bit more in parking fees than shell out money to fix that scratch or dent.'

jermync@sph.com.sg