hi, Well I'm not really the best person to get advice from as there are many people from here who know alot more than I do. Basically most people moddeling a low poly car set them self a budget could be 5k polies could be 30k, (30 k usually considered mid poly). Usually there are more 3 point polygons used for low poly moddeling rather than the usual 4 point polies when moddeling with a subdiv smother
There are a few diffrent ways to smoth the model, i usually go to options and put the "smoth" on the car and set it to 60, yet there are many diffrent ways im sure im just used to doing it this way. I cant really give any tips on how to model in low poly as we all model very diffrently
emm what i do, do to bring out shaper edges, rather than using a low number chamfer say .2-.3 i will select the edges i want and slick "split", i find this keeps the poly down and gives the edge a nice look
IMO
Cant really say i have helped you but hope it has given you a reasonable ammount of ideas and what to look for, also looking through smcars and a few other forums may be a good idea to look at other low poly cars to get an idea of how they are moddeling an some of the tequniques of how there doing it