I am a beginner and don't fully understand pricing for google image ads.
Is the cost only related to your bid for clicks, impressions and/or action?
Does the size of the ad affect the price? or does the larger sized ad just bring a higher necessary bid?
Tell me the prices in INR.
Pricing is based on your Bid. Here is a great new Video from Google about how the Ad auctions work, I think it will be beneficial
In Display Network, you can bid on Cost Per Click, so you only pay when someone clicks your ad, ( recommended) OR on a Cost per Impression model.
Sizes of Ad doesn't directly effect cost, but you may have to BID more to win the "auction" for the larger AD SPACE spots.
Hope that Helps