1- Size: do you need a Smart car or a BMW X5 (i.e. what are the dimensions of the LED screen you want to install?)

2- Power: do you want to drive it at race circuits or you need it just to do the grocery? (i.e. what's the resolution of the LED screen?). Note for beginners: resolution = distance between the pixels: the closer they are, the better is the image at shorter viewing distances.

3- Reliability: premium car brands use premium materials and are therefore able to provide longer warranties (i.e. so do LED screens' manufactures)

4- Credentials: how much do you value the world-class service provided by Toyota? (i.e. beware of newly established Asian companies without a proven technology and history)

5- Training: BMW gives a 2 days safe-drive course to any Customer that purchases the new sport series. (i.e. beware of LED screen manufactures that offer no or minimum training on how to use the display effectively)

Before purchasing a LED screen you should ask yourself these questions and rank them depending of the importance that each point has for you. In this simple way you can define the specifications and profile of the ideal screen and manufacturer you are looking for.

Now, if you need to have exact numbers, here there are some real figures:

1- Size: the smallest led screen size I recommend is 2 x 1.5 meters: of course it depends on the pixel pitch, but in general that's the smallest size I recommend.

2- Power: the best price/performance ratio resolution I recommend is 10mm: again, the resolution depends on the average viewing distance of your audience, but in general 10mm is a safe bet.

3- Reliability: the warranty should be ideally 2 years or more. some entry-level products might have a 1 year warranty. If this is the products you are looking for, make sure that maintenance contracts are available. And if they are, beware of companies asking 25% of the value of the screen starting from the second year for maintenance it might mean that they consider their product at risk.

4- Credentials: for the credentials of the company I recommend you don't only check the website because anyone could insert a nice picture on his website (e.g. there are a few pictures of an Italian manufacturer screens published on other websites). What I would recommend you to do is to get the name of at least 2/3 Customers that are already using the screen and then talk to them. Or ask for video-testimonial (indicating the details of the person speaking).

5- Training: concerning the training, make sure that your supplier can provide you at least a basic training on how to use the screen. I'm not talking about a technical training (that's should be obvious) but I'm talking about a training that shows you the best techniques (and the worst mistakes) to create ads, market your screen, find and win advertisers etc.

A final note concerning the price: if you are approaching the LED screen industry for the first time, I think you should consider a minimum investment of about 20/30.000 Euro to purchase a display similar to the one I described above. If you get an offer for a lower price, go through the 5-points-checklist and make sure you are aware of what kind of LED screen you are getting.