What does ROI mean in connection with satnavs?

Renault mengane fuel light always on gauge not working? How many gallons does the gas tank in the 2008 Maserati Quattroporte hold? Diagram of front suspension on Peugeot 406? Will timing belt breaking on citroen xsara Picasso 1600 petrol 2001 model cause the valves to bend? How many Mercedes SL 55 AMG were made in 2006? Where is wiper relay located on Audi a6? What is the PMS color for BMW logo? How do you open the gas door on 1993 Mercedes Benz 190e? Is a Lamborghini faster than a Roll Royce? Do you have to remove the seat for the battery of a citroen xsara Picasso? What number fuse for rear lights on peugeot 307 sw? Where is the fuse for the door locks on the 2000 infiniti I30? How do you replace spark plugs on a seat ibiza 1.2? Golf 4 gti oil press warning light goes on when car is rev'ed even though the dipstick shows there is enough oil in the car.What could be the problem? Can you fit a sat nav into a megane extreme 10 plate? What must you have in your car whilst driving in belguim? How many seats does a lamborghini have? How do you open bonnet of Renault Kangoo? When was the Peugeot 305 XSI manufactured in France? What is the turning circle of the 2007 BMW Alpina-B7?

What does ROI mean in connection with satnavs?