See friend in engineering college ,the fee varies from college to college and government fee and private fees are also different. Eamcet is the common entrance to get admission into engineering and medical seat.This exam is conducted by osmania,jntu,sri venteshwara,andhra university.

With 50,000 rank,its not at all posible to get good college .You can get colleges which are recently established or has poor rating. Better and good college seat would be reserved by top 25,000 rank students. Better to attend all the 3 counseling. No doubt with this rank also you will get admission in engineering college. The fee for engineering college would be minimum of Rs 40,000 -60,000/year.(as per your rank). Do not worry about the college fee,you can apply for scholarships in each year.