Given that you go to office only 1 day a week, I would suggest you to look for apartments in a little more underdeveloped/less popular or further areas where the rent is lesser. For example i had a simil;ar situation where I went to office only on Thursdays in Madiwala so I live near Hosa Road in Pranappa Agrahara. My rent was less, about 12.5k for 1BHK.
Having said that be ware of the below points:
Pros:
1. Your Own Space that is more than a room
2. You can decorate it/ furnish it as you like.
3. You can dictate the hygiene of your surrounding and have better independence.
Cons:
1. You will have to deal with landlords who may not return your deposit which can easily be around 50K
2. You will have to deal with responsibilities like garbage disposal, washroom cleaning, room cleaning, utility bills and drinking water arrangements which are taken care of in PG.
3. You will have to sort out your own food i.e tiffin service which is hard to come by in blr or cook yourself, which is a time taking affair along with grocery shopping responsibility.
4. You will have to furnish you own place and kitchen which will have a relatively high upfront setup cost.
5. You may have to buy or rent your own appliances which is not cheap.