The cost of extras is a mind boggling view! How DESPERATE are you to have, say. leather stitching in a non standard colour ? Then see how much to basically swop the bobbin on the sewing machine! Paint colour is another. Unless specifying a special paint then fairly minimal cost of new paint. There are serious mark-ups. It’s the same for just about every car. Mainstream you get a few model choices with “ upgrades” to the features. A few accessories to add in ( often thrown in by the salesman to clinch a sale. Standardised production to , say, 4/5 model options to streamline the production line. How many do you end up never using? With a low volume company hand building then there is scope to offer personalisation. It is a damn good profit generator! I used the CX configurator when launched. Started with the basic spec then added on, for me, essential extras ( luggage rack). No fancy bling, just a “ poor man’s CX spec”. It is easy to see what extras you can get then think “ it’s a one off so ok, let’s do it. “ hmmmm the wheels look nicer.....change the colour of the roof......dash spec..... Try it! Resale value......yes some options make the car LOOK more desirable and help the sale but to what recouping of up front outlay? Same as selling a house. Initial impression helps to ease into the sale. My thought process is one of when work is needed to replace parts then how much extra to upgrade? Brakes.....upgrade to stainless brake lines instead of new “ rubber”. Dampers....upgrade or original?