MBA/PGDM

As per your records, 40 percentile in CAT won't fetch any decent college. But what you can do is choose a distance learning course for Masters if you think scope of improvement is less as you need to score decently well in CAT as graduation marks are also on the edge.
Else try for next year and prepare well.

I will keep this answer as short and accurate as possible.
It depends on how you define decent college but 90+ overall and in both sections should suffice.

Hi Gaurav,
GD-PI is an important criteria for selection to all business schools. It is an interactive form of assessing the personality, communication skills, content and body language.
Thus, you must pay good amount of attention for the preparation.

Check out various entrances at first and meet their deadlines . Upcoming entrance exam is the MAH-CET.

The fee structure for MBA ranges from 8-10 LPA. This information may vary as per institute.

Part time MBA is possible with a job. Make sure you devote your time into studying on Saturdays and Sundays.

Above 85 in CMAT and MAT will fetch you good colleges.

Try giving another attempt and give the MAH-CET exam, aim higher this time as it's very much easier than CAT, as well as it is easy to crack. Doing so, you can aim to higher and better colleges in the city.
With 65.86 you would get average institutes.

For MBA (PGDM) you can apply in IES, MET, Thakur, Saraf, Welingkar, etc. You need to perform well in GD/PI to make it through these colleges.