Want has turned to need as 11 year old sedan is nearly kaput. Ideally want a Sporty and Fun 2-door car with Rear Wheel Drive that will legally seat 3 people - if needed - but will primarily be used by just One. Ideas?
Lots of choices, how much money are you planning on spending?
How much are you willing to spend? There are cars like a Porsche 911 that have a rear jump seat that could accomodate someone very infrequently. But even older ones are not cheap. A Mazda RX-8 costs less and has real seats in the back, even if they are hard to get into. Other possibilities are 2-dr coupes, like BMW 325Ci or a Benz CLK. Another car that’s lots of fun is an Infiniti G35. None of these is inexpensive. You could find a 2003 G35 Coupe for $17,000 for instance.
Mustang?
I would highly suggest a BMW 1-series(new only) or 3-series coupe(used/new). Another great choice is the Mini Cooper which is an absolute hoot to drive and delivers great MPG in the package.