Hey newbee,
Not sure if i can help as i'm just starting out myself. But location was definately the make or break for me, especially being based in London.
It's taken me 4 years to figure it out.
I had to first locate all existing businesses, no matter how small or large they were within, say a 1 mile radius, for my locality, it was the city fringe.
Then it was a case of pin pointing a good clear empty patch on the map. There were a few clusters on certain high streets, so I avoided those (as a newbie, I'm not ready to go up against the pros)
Then noted how close it was to transport connections.
Then how close it was to clothes/ shoes stores (where the material girls would hang out, lol).
Obviously researched the demographics of the location, present and future,i.e. what is the current density of the local population, what kind of social bands they fall into (income bands, young proffessionals?) and what are the future prospects for that location (and new upcoming housing developments, coffee shop chains popping up?)(beginning to sound a like property tycoon)
Then I waited, for the past 4 years I watched how the Industry market moved and how the locality had developed..
Obviously, i'm sure you don't want to wait years, but my best advice is to know your location. You may not be able to obtain desktop info such as income levels and the local population make up, so it helps to learn and know the community, as much as possible. Then I guess you'll have an educated intuition?
Oh, I don't know if the other geeks would agree, but how important is to be next to the foot traffic (as oppossed to being on an off road) and does what the neigbouring businesses do matter (cos i'm sure being next to a chippy, or yes, being opposite the competition doesn't help)?
Anyways, my method isn't exactly text book stuff, it's just kinda the way I did it. I hope it helps still.x