Diploma

Generally speaking, the fees for PG Diploma in Aviation Studies from any institute ranges from INR 50,000 - 70,000.
You will, although, have to confirm the fee from the institution you are interested to enrol with because the fee varies from city to city for certain institutes.

Yes, you can go for cabin crew/air hostess job provided you have cleared class 12 before pursuing the diploma.
The minimum eligibility on the educational background is 12th to be a cabin crew.
You should also check the medical standards required for cabin crew.
The minimum height for female candidates is 167 cms. The age should be less than 26 years for freshers.

I would say a degree is much better. You'll have enough time to have hands-on experience and then placement.

Hi,
Both are beneficial whether you do M.Com or any other Diploma. You can pursue below mentioned 1 year courses:
1. Accounting/ E-accounting.
2. Financial tax.
3. Banking sector. ICA is the best institute for the same
Regards.

Hi Ramachandran,
You have not mentioned any institute in your question. Basically, it depends on the institute whether they consider you eligible or not.

Go for Masters degree.
Get placed in some hotel industry.
Don't go for the diploma course.

Evening/distance/online/part time engineering courses are not valid any more as per the latest supreme court verdict, hence would recommend you to join regular B.Tech course for better career prospects.
http://www.tribuneindia.com/news/nation/no-technical-education-through-correspondence-says-supreme-court/491819.html.