Well never calculated the cost but I did it as follows.
- Roof: the most important as there is practically nothing above the lining hence the car gets so hot during summers. I simply took off the lining which is just pasted with samadbond and use thick foam which I guess is called jambolen and is easily avilable and gave the car to suzuki to reinstall the roof which was for 1200-1600 rs if I remember correctly.
Floor and trunk: the same and can be done at home with limited tools
Doors: I used U seal ..got the rolls from states for my reborn and Wish but alot got left so used it (you tube it, being used as an alternate to dymanat) and you can use any other alternate, people are using the same foam for doors aswell.
Result: relatively quieter and the cheap sound of door closing gone to a acceptable level but the roof was the real winner, as it used to unbearable to sit when the car used to be under direct sun but now it's just like any other civic or Rolla and cools by within mins.
Hope that helps.