I was ready for my skill test but couldnt take it until i finished my exams, Thats when i let everything slip for over 2 years, so when i went back i basiclly said' Id love to go flying again but need to just hammer the ground school and pass all the exams before i start flying again.
The CFI took me under his belt and got me through it all, Then i passed
I paid for a lot of ground school through it all but some people have no trouble learning it from the books at home.. The cost is simlar to all the local flying schools. So yeah expensive :-(
Good luck