Keep an eye out for flyers and posters dotted around your neighbourhood advertising upcoming boot fairs in your area, or visit carbootjunction.co.uk to choose a location.
First, go as an observer and see where the best sites are located; often these are close to the entrance or food stalls.
And have a look on eBay the night before to get an idea of approximately how much the things you're selling are worth second hand.
Decide how low you're willing to go before you have to refuse to part with an item, so you aren't pressured into selling something for much less than you'd like to.
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2. Pack the night before
Put your items in boxes, so you can quickly load your car in the morning. Take a paste table and sheets to present your goods, and make sure you have plenty of loose change and plastic bags for people to carry their newly purchased items away.
If you have a lightweight gazebo for the garden, you might want to pop it in the car if the weather looks bad; not only will it keep your possessions dry, it will lure over people who also want to avoid getting wet.
Consider taking a thermos of tea and a breakfast sandwich. If your stall is busy you might not have time to grab anything; plus you don't want to fritter your hard-earned cash on lukewarm tea and a bacon bap from a burger van if you can avoid it.
3. Get there early
A successful boot fair involves a very early start, sometimes as early as 5am to ensure you arrive before the seller's opening time.
You ideally want to be one of the first in the queue in order to choose your high-traffic site; if it's wet weather, look for dry areas.
And bear in mind that as with seasonal sales, serious buyers arrive early.
4. Go with a friend
An extra pair of hands can be useful if you experience a sudden rush of visitors to your stall, or when you need a break, and to keep an eye on your goods if you're busy with an interested customer.
And if you happen to excel at something other than quick, in-your-head arithmetic, find a friend who can do adding up and taking away without breaking a sweat, so you don't have to fumble with a calculator.
Having someone to pass the time with will prevent you looking bored and unapproachable; though be careful not to get so engrossed in your conversation that you miss a prospective would-be customer's attempt to make eye contact.
5. Consider when to use price labels
Not pricing everything up can save time, and people may pay more than you expect for an item, especially if it's something particularly collectible or nostalgic.
If anything has an interesting backstory, consider leaving a price off, as you might be more likely to make the sale if you build up a rapport with the buyer.
However, if you organise a bargain bin or rail with a label declaring 'Everything 50p', that could attract people of a shyer nature, who would rather not be talked to as they browse.
Where else can you sell unwanted possessions?
6. Bargains attract
Eye-catching signs often work; BOGOF (Buy One, Get One Free) or you might like to try a couple of more creative ones like 'Treasure Trove' for some of your older items (jewellery, ornaments, pictures, etc.)
7. Prepare answers to objections that buyers may have
'Does the torch work?' Have batteries with you.
'It's too expensive.' Know the recommended retail price and respond with 'Brand new, this would cost eight times the price'.
'It's awkward to carry.' Have bags at hand.
'How does this work?' Include instruction booklets.
8. Set your stall out like a retailer would
During summer, organise plants, garden shears, gnomes and parasols in a prominent position.
Place all-year round items such as books in a 'Great Reads' box.
If you're selling clothes, use a clothes rail, perhaps organised in sizes, or divided into men's, women's and children's clothes.
Periodically view your stall from the front as a customer would - what would appeal to YOU if you were passing by?
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9. Charm sells
Be polite and upbeat, and show interest in the customer; this has a huge effect on sales.
If someone is interested in the camera, ask them questions, for example; what type of photos will they be taking? Do they print their own photos?
They may also be interested in filters and a colour printer, especially if you show them how they work.
Be confident in your approach: if you are unhappy with an offer, politely say no and tell them why you feel it's worth the price you are asking, but be prepared to bargain.
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10. The final clearance
If you want to go home with an empty boot, use your vocal chords to good effect and let customers know of some great tactical combinations, for example; tennis racquet and 10 balls were £15, now £9 for the lot.
Above all, enjoy the fun of being a seller.
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