1. Trade on eBay
Figure out what's selling on eBay, then invest in setting up a professional-looking eBay shop from £14.99 a month. Popular (the new version of eBay Pulse) is a great way to spot what people are buying.
Once you're ready to go, check out our tips for selling on eBay here.
Sell good quality digital photos to sites like istock.com, shutterpoint.com and fotolia.com. But be warned: this is quite the slow-burner. If you dream of becoming a freelance photographer, check out our free guide here.
Invest in a good cookery course, then start offering your services to friends of friends in need of dinner party assistance. If you want to make it big in chocolate, check out these great tips.
4. Become a cookery writer
As above - then publish your own cookery book through blurb.com. Sales will come in from the site, and you can sell yourself to new prospective clients by saying you're also a cookery author.
Do some serious homework on cheaper pieces - invest in an encyclopaedia and read mags like this one. Buy a few items to hedge your bets, then sell to antiques dealers and shops.
Proper training courses are several hundred pounds at least (recommended ones here), but if you're a marathon old-hand or a gym-bod you could entice some clients without. Pick up part-time work in a gym to find clients.
You can buy a stall for around £100 - £150 (from somewhere like this). Make sure you comply with all health and safety regulations and get a license from your local council if you're selling alcohol, hot food between 11pm and 5am or food from a stall or van on the street.
If you're looking for more tips, check out our guide on how to start a market stall here.
Supply the midnight masses and charge a premium on booze and snacks delivered after pub closing time. You'll need a personal license to sell alcohol, which costs £37 - get it online from your local council.
Start this business with no overheads by using clients' cleaning products. Pay for Disclosure and Barring Service Checks (£26 each) for yourself and any other members of staff to reassure new customers once you get some money coming in. With these top tips, starting a cleaning company is the easiest way to change a chore into a business.
Target small businesses at networking events and with flyers to user-test their new products or websites. Then place free ads on Gumtree to find participants and skim a fee off their hourly pay. More info here on conducting focus groups.
Call around all local business and clubs and say you'll find them someone to hand out flyers for a £3 charge (on top of their hourly rate). Then find students in need of work on Gumtree.
Decorate your living room, stick some posters in your front window and start a restaurant in your house. Technically you're meant to get a load of health and safety checks done for this, but there's a whole crop of people doing it on the sly. Check out our guest blog from Horton Jupiter to find out how it's done.
You can start this business for next to nothing. Do some research on your local area and plant clues for family fun days and cheap office outings. Take a look at how Hunt Fun and Treasure Days are doing it.
The whole of the middle class is into organic and home-grown veg these days, and with packets of hundreds of seeds coming in at around 60p, you can sell your own produce for a whopping profit. Or just take clippings of plants and herbs you already have, grow out into separate pots and sell to neighbours and friends.
Got green fingers? Put them to use by offering your services to people in your area. Show them sketches of how you think the garden could be improved and you become a landscape gardener to boot (though you'll need to do careful research on what grows well in which places and at what times of year). For some helpful hints, read this free guide.
Capitalise on people too busy or too lazy to cook by offering to deliver delicious dishes of their liking, home-cooked by you. Check out our interview with the founder of The Pure Package for inspiration.
Armed with nothing more than a map and a book on local history, you can guide tours around your local commons, hills or towns and share insight into the history of your area for a small charge.
Basic needlework is astonishingly straightforward. Offer to darn friends of friends' clothes for a nominal fee and take in too-big shirts and skirts.
Knocking up ribbon-adorned wicker baskets brimming with Bon Maman jams, freshly-baked muffins and fruit is relatively cheap, but you can charge a premium.
Easy if you know how. Getting a formal qualification will improve your chances of doing business with people you don't know. Check out the Association of Pet Dog Trainers for more info.
Most pet owners prefer one-on-one TLC for their animals than putting them into kennels. Keep your rates competitive and incentivise clients to refer a friend.
Perfect if you've got a natural knack for organisation. Establishing cut-price deals with catering companies, florists, wine suppliers and the like will ensure you offer a competitive service.
Have a proper clear-out of your junk to get started, then reinvest profits into buying stuff from any charity shop you have time to scour. Offer to take friends' junk off their hands to cut overheads.
More and more small businesses are latching onto the fact social media can help them, so offer to maintain accounts for them for a small fee - you can keep business ticking over while still doing your day job. Tools like Tweetdeck will help hugely. More advice here.
There are gutters to clean, tiles to be scrubbed, lawns to be raked and paths to be laid all around the country. Post friendly notes through letterboxes advertising a cheap hourly rate.
If you've got a degree, or good A-level results, you can offer to help out schoolkids with their homework and exams. Get a certification to make it more official if you struggle to find work.
There are still millions of people out there who feel utterly confounded by computers and the internet. If you're a spreadsheet whiz or an Outlook old-hand, you can charge them for lessons.
If you've made it through the rat race and come out the other side older and wiser, you can help newbies tidy up their CV's. Advertise on Gumtree and ask friends, and keep fees low.
Get yourself down to a retro clothes market in a university town, armed with piles of 70s, 80s and 90s clothes from charity shops, and you'll find you can charge anything from £5 to £50 an item. Ask the local council about renting a stall.
What business to start?
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