Often there is a railing or fencing behind you , but nothing in front. And while you might get away with two ropes behind , you can't beat 4 if the wind is up. This is why I carry the containers about a third full, as by tipping the contents of two into the other two, I have 2 anchor points to the front of the booth without having to find a tap.

Even a third full they will do for a mildly windy day . If winds were stronger I would have to find a tap and put more water into all four ...but luckily I have never needed to do this yet. But it's best to have them onboard anyhow just in case... (I don't travel with them full up , as it makes them lighter to carry.)

Tony James writes:
I fasten the frame legs to the ground and use a cordless drill to make holes through the cement between the pavers. No good for solid concrete or similar surfaces. I use fine pins and they keep the frame upright when it's dressed because it's the wind hitting the cover that causes the problems. Once guyed it's ok. I use the drill also to open holes for the main guyline, carrying thinner and shorter pins than I would use on grass.

One advantage is that once in the short pins will grip and hold between the pavers because they're tight. The same pins would pull out of grass far too easily.

I carry S hooks to fix guy lines to furniture or anywhere there's a purchase. Pointed butcher style hooks grip better than plain ended but beware the health & safety people who consider them hazardess - put some tape over the unused pointed end.

Chris writes:
Another approach is to use something heavy to tie to the frame. Geoff Felix (who travels by public transport and therefore couldn't use your method) uses the trolley, on which he wheels his gear, to tie to the frame and add some stability.

I have a couple of heavy wooden planks which lie on the ground and the frame legs attach with nylon cable ties and large screw-eyes.

Another traditional approach is said to be to have a footboard on which the showman stands, his weight holding the booth down. I have never quite understood this idea - surely he has to leave the booth sometime? What happens then?

Eric Sharp had a practical idea with his aluminium outdoor booth which he used to sell - this had stabilisers which folded out from either side of the base. These could be pegged down on grass or sand, or if on a hard surface you could park your car with one wheel on the stabiliser on the windward side. I have used this system and it works a treat.

At one of the National Trust Properties I work they have a number of small quick erect marquees. These they use on hard surfaces and have a number of small sand-filled bags (each perhaps one cubic foot) which they use as anchorage points. They use two or three bags at each point. One large bag could of course be used - but small bags are easier to carry.

Special sand bags are made of a strong, tight-weave material. As well as being available from marquee suppliers they are available from theatrical suppliers (they are used to anchor ropes used for flown scenery).
They can be purchased empty (about £7), or filled with dry silver sand (£1.75 extra). You can also buy Weight Bags, empty, and then fill with lead shot which you can buy by the kilogram.