This is based on my last trip to BZA. The station as all know if absolutely big and real heaven for rail fans with dozens of trains arriving and departing every hour! (Sorry for being long post)
Food options:
The station is very clean as staff are working very well. The PF 1 side has various options for food named as Rail Dhaba like curry kitchen for south Indian dishes, then Madras coffee point which serves filter coffee which is a little expensive (Rs.19 for a tiny glass).
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premise also has a small counter of KFC only serving their chicken items and no burgers. The water filling point is also conveniently placed beside these food joints.
Then of course many small refreshments joints selling butter milk, lassi which is absolutely required for such humid climate. There are also fruit juice shops selling juice for Rs.20 for Musambi, pineapple etc which was very good and refreshing.
Facilities:
As many commented there are AC waiting hall and other regular passenger halls. I was surprised not to see a single escalator in entire station premise (I hope there are escalators, please comment). It is a big requirement for such a mammoth station.
Transport options:
a) From PF#1 side (easter gate) there is a prepaid auto stand. Please don't give your ears to the auto guys who come to you asking if auto needed. Just walk outside from PF#1 side to see the police counter, get auto from there. From my experience I see the difference in fare between normal auto and prepaid auto was ~20-40 Rs. It may be more if they see people are new and unaware of facilities. So prepaid booth is very useful.
b) Just adjacent to the prepaid booth is the bus stop. There are several buses departing from here. I understand you can almost board any bus to take you to bus stand. If your target place is Kanakadurga temple, then there are frequent buses (at least once in 10 minutes which I saw) styled like Tirumala Tirupathi buses, if you are familiar with it. Caution: If you see the bus a little crowded, please avoid as it becomes more crowded from bus stand as it goes through this route. In humid conditions, such crowd and heat will not
give a goods experience. The fare though is just Rs. 10.
Instead if you are not tight on budget, please opt for prepaid auto which may be just around 50rs or Ola auto for ~70rs.