For living Indian style its enough. But once u come here and look at things and depending on your desires and needs its very less. 

Never compare u r salary with other nationality, when u compare its peanuts. 

For prinicipal of International school, with my knowledge its peanuts. U said accomdation will be provided, is it 2bhk or 3 bhk or compound vila, its all matters.

Regarding schooling to ur kids, which school, the same school where u will be principal or different.

chafuer driven car - will it be only for official purpose or even after office hrs, as transportation is very bad, in that case u might have to obtain a licence and car - for that cost nothing has been mentioned.

Hope this details will help u to negotitate or decide further.