**1/12 -2wd straight axle "pan car"-uses foam tires -simple suspension -attention to detail is key -4cell or lipo, classes from 17.5 to mod -Can am/ Lemans style bodies
**World GT -2wd straight axle "pan car"-uses foam tires -simple suspension -considered easier to drive than 1/12 -13.5 motor, 4cel or 1s lipo -2 door gt style bodies
**mini cars -Tamiya 2wd or 4wd by other manufacturers -cheap to start with -easy speed to handle -full suspension with limited adjustment -6 cell or 2s lipo -most times limited to 540 silver can -scale looks
**sedan -4wd full suspension, full adjustment -usually 6 cell or 2s lipo
-breaking this down further...
Rubber tire- all motor classes run -rubber tires are considered easier to deal with than foams by many (tires remain the same size), work on a wide variety of surfaces, more forgiving than foams in terms of handling -bodies shaped to perform best
Foam tire -all motor classes run -foams provide maximum grip and corner speed, almost always hook up on carpet or prepared surfaces, can provide razor sharp handling (some times too much), more work due to changing tire sizes -bodies shaped to perform best
RCGT -17.5 motor -uses a spec tire in 2 compounds -realism is stressed in body selection -similar to rubber tire, but slightly slower
Trans AM -21.5 (limited gear) or 17.5/27 w/4cell -uses a spec tire -realistic muscle car bodies -close racing because of slower, beginner friendly speeds -similar to rubber tire, but cars have little aero help and less overall tire grip
Overall, i would recommend trans am to start with. You can easily run an older chassis and be competitive (think TC3) while learning how to tune for on road, and have a lot of fun. If you don't like it, you probably can sell everything pretty easily. RCGT is similar, but a little faster.
1/12 is awesome and pretty cheap, but they are sensitive to adjustments, and it really is best if you have someone who can guide you in building and setting up the car in the small details.