Nice work Nikki I can offer some suggestions.
#1 the car seems dull (no contrast) like it was lightened too much in PS it needs to be blended more with the background, also the car fills too much of the frame, it would be better about 4 steps back.
#2 the car is too centered, it would look nice if the car was cropped to the right side. The post without the boat looks great but I would also suggested cloning out the white parking lines as they are distracting and easy to remove.
#3 Nice but looks like a snap shot, maybe if you turned the wheels or shot from frogs view it would help.
On the last set you posted the WB it too orange, are you shooting raw?
***Wallpaper of the month***