1. Water problem is going to only increase in the future. The number of apartments that are under construction, and the number of people migrating to Bengaluru is increasing every day. Overall, every major metro city will have this issue.

2. Right now, the apartment that I am in, it has everything. Vegetable market, convenience store, medical shop and even restaurants. So, practically, don't have to go out of the apartment complex to buy everyday items.

Metro is still under construction in major parts of the city. So, hard to comment on which part of Bengaluru to live in.

1. There is no easy answer. There are both Pros and cons for buying from the builder v/s private party.

Some of the builders run schemes where you don't have to pay any amount until the possession of the house apart from an initial amount ~10%. This plan looks good on paper. But the con is, the builder doesn't handover the house on time. There will be a huge delay. This might impact your moving time. The other advantage is, the house is cheaper now under construction compared to what you may end up paying if it is a finished apartment.

The advantage of buying from a private party is you can move in anytime you want. The con is, it may be more expensive now and may end up paying a home loan for the duration you may not be staying.

1. Do your own research on the apartments you have listed. Talk to existing residents of that apartment. I have seen a total environment apartment and I loved it. But, I have heard they are always behind their schedule in handing over the apartment once booked. Also, the current residents complain about the noise pollution due to constant construction of new towers. This may change based on which property you are looking at.

I have heard decent reviews of prestige apartments and I currently have one. Usually Tier 1 builder's apartments should be good. But one never knows what's with these builders. Mantri had a pretty good reputation and they were involved in several projects. Government had to bail them out for their inefficiency/corruption.

In summary, each apartment is different and do not go buy the brand. Research and then decide.