For a budget and solo trip to Varanasi you can take the expenses around 6K including hotel stays.Budget hotels are easily available near the railway station and around ghats.
If you want budget trip you can easily avail some hotels near Cantt Railway Station. Exploring Varanasi isn't costly coz local transport is really good. Including hotels you can make it under 5K. Make sure to enjoy the street food of Banaras.
IN Banaras it will not cost you more than 5-6 thousand ( budget hostel and home stays are available) however you need to consider the travel cost also from your hometown to Banaras
IN Banaras it will not cost you more than 5-6 thousand ( budget hostel and home stays are available) however you need to consider the travel cost also from your hometown to Banaras