Wimbledon fortnight starts on Monday and this year more local residents than ever before are preparing to let their homes out.

“The chance to make a substantial amount from a short let is encouraging more people to rent out their homes to players and fans,” says Joanna Doniger of Tennis London, which arranges accommodation for players and sponsors. “No one’s getting any income from deposit accounts so they are looking for other ways to make money.”

She says there is big money to be made from renting out homes in the London SW19 area close to the tennis tournament . Weekly rents can range from around £1,200 for a two-bedroom flat in Southfields to £2,500 for a two-bedroom flat in Wimbledon village, or £5,000 for a larger property overlooking the grounds.

The Edinburgh Festival, which sees more than 3m visitors descend on the city, also presents opportunities for homeowners.

Jason Redman, owner of The Festival Partnership, which specialises in renting out private homes during the festivals, says: “Rents have gone down by between 10 and 15 per cent this year because of an increase in the supply of properties. But it is still possible to get 2.5 times what you might usually get for letting out your home.” On the agent’s books this summer are one-bedroom apartments for £1,600 a month, and four-bedroom properties costing more than £3.200.

With the London Olympics and Paralympics in 2012, thousands more Londoners will be tempted to short-let their properties.

But potential landlords need to think about costs, say experts. Agencies usually take a commission of 15-25 per cent and may also charge registration, inventory and/or contract fees. For short lets, the cost of utilities apart from telephone, is included in the rent.

Insurers must be notified as letting a room or a property may affect cover and raise premiums.

Experts also warn that anyone letting their property needs to declare the extra income on their tax returns. Anita Monteith, tax manager at the institute of Chartered Accountants for England and Wales, says the Revenue is expected to be vigilant this year, sending out “enabling” letters to local residents pointing out the need to declare income and scouring the windows of local newsagents for lets.

Some generous tax breaks are available. Rent-a-room relief allows people to earn up to £4,250 a year if letting part of their property, but only if the homeowner continues to live there.