Neighbour creating problems

Dear Friends,

We are living in a 4 Flat / Apartment building in Chennai. This building was constructed by builder and sold to 4 different people with the general intention and assumption that  they should cooperate and live together in Harmony. No society or trust is formed between these four people.

Now out of the four flats , two are occupied by owners themselves (ie. Myself and other person (A & B) and the rest two are rented out to tenents by their respective owners (C & D)

Now the regular maintenance cost is being charged from the tenants but as the flat keeps on getting old some repairs need to be done which are mandatory and cost high but need to be done at earliest.

In this we are not having problems with owners A  & B as they understand the situation and are giving money for such works. Only issue is with owners C & D who have let out their apartments to tenants and every time they need to be contacted and explained the issue and money needs to be taken from them.

The owners dont have any pakka agreement with the tenents which speaks that major repairs should be borne by whom but in general the owners are bearing the repairs cost as tenant should not be taxed for maintenance fees other than the specified amt per month and it is responsibility of the owner to see that his flat or general area is in good condition irrespective of whether he is staying or renting out the properyty.

Now the overhead water tank is leaking and the two flats in first floor owned by owners A & B are having water seepage and immediately needs to be repaired / replaced  which is costing huge amount. 

So the below is the details:

A - As the owner (i.e myself) resides in first floor the owner is ready to spend

B - As the owner resides in first floor the owner is ready to spend

C- The owner has let out the property to tenent and the owner is called and apprised of situation and has agreed to spend.

D - The owner has let out the property to tenent, and in this case tenent is giving misinformations to owner regarding the flat conditions, The actual legal  owner of Apt D,  is the daugher of mom & dad, and they bought the flat in her name , daughter is married and lives abroad and has just flat as investment to her name, all the other works and letting out things are looked after by her mom & dad, i think you understand typical indian mom & dad who are looking after the flat, but the registration is in daughters name. In past also the owners D i.e parents have been contacted and they have given money, but this time they are not responding to our calls (owner A & B)  and we are facing issue in repairing the flat.

We are trying to amicably solve the situation, but are literally being harassed by the mom & dad,  but if this has to be taken legal how to take it legal , since the actual owner is abroad (singapore)  , can we file case against the daughter and send a copy to abroad police department so that she gets notice in abroad and the parents realize their mistake and give money for common repairs which are mandatory.

We are trying to avoid going legal way but they are not listening so we dont have any option, also we are simple people and want to live our own simple life and we know legal going will take  a long time, till then the flat will be completelely spoiled.