Mini-van for bicycle
If its just yourself and one road bike, it will fit into the back a majority of hatch back style cars. With the seats folded down and front wheel off, you would be surprised how much space even a compact has. 

Look for a car that suits you best then make sure the bike fits. As far as putting the bike in, look for rear seats that fold up quickly and easily, a wide rear hatch opening with a low sill would be important to me. A front passenger seat that folds forward (if a small car) might help. 

Another option is some cars allow the rear seats to fold up, meaning the bike could be carried in the rear passenger foot well.  In this case you may want a chain cover to prevent oil getting onto the cars interior. 

Consider how much time the car is used as a bike shuttle vs other uses and balance the the convenience and costs.  For instance a large car that you can leave the wheel on is more convenient but probably costs more to own and run, a small two seat sports car while  cool to own,  is not very convenient if you have to take front and rear wheels off to carry the bike.