My family recently opened a fruit stand approximately 15 miles outside a city in northern california right on the highway. There are no other stores around, or homes, and there is none for another 30 miles, so it feels like it's in the middle of nowhere. The business is doing very good so far so I thought it's time to spend some money on advertising.
Driving to the store from the city there is a billboard for rent. I haven't called that number yet to ask for the cost but I do want to rent the advertising space since the billboard is in a good location (it's visible clearly from the highway, no other billboards around, basically you can't miss the billboard since it's on a lonely stretch of highway..).
Since the store has very low prices, even compared to the produce sold in flea markets, I thought I would advertise in a way to emphasize low prices and also "excuse" our location. I came up with this:

"Our competitors did not want us near them,
so we opened in the middle of nowhere"

along with the logo on the lower left side of the billboard and "x miles ahead" on the lower right. I need some help revising the ad since it is too long for a billboard, but keeping it simple and funny at the same time. I also don't want something like "low prices, good quality" or anything along these lines since it is cliche and I want the driver to have to think about the ad and why wouldn't our competitors want us near them until they get close to the location. The drivers will have time to read the entire ad, even though it's long, so should I revise it or is it ok to break the "no more than 6 words" rule?

I thought the rule was no

I thought the rule was no more than 8 words. At any rate, that rule is pretty flexible depending on how congested the road is (i.e. how slowly traffic moves). Billboards along the freeways in LA run pretty long, for example. Also, I wouldn't really count words like "to", "and", "is" etc. Here are some ideas off the top of my head:

Prices so low they decided to banish us.

Crazy location, nonsensical prices.

Get to the fruit before the coyotes get to us.

At least we're not in Fresno.

You don't really have any other choice.

It's not like there's a Wal-Mart down the road.

The middle of nowhere's best kept secret.