PPC is the most popular form of advertising and is preferred if you wish to get traffic to your websites. However, it can be expensive if there is a lot of competition for your keywords. Most advertising networks offering PPC usually have a minimum cPC of $0.05 (about Rs 2.5) , for getting a visitor to your website. PPC advertising campaigns are also complicated to create and manage.
If you are selling a product, you also have to pay an additional amount to the payment gateway for processing the payment and completing the sale.
Currently, at least in India, marketplaces are a much cheaper option for selling your product or to atleast gauge the market demand for it. Ecommerce marketplaces charge Rs 1 per listing for a week or a flat annual or monthly fee depending on your sales volume or number of products listed. This can be very cost effective if 5-6 prospective customers see your listing and the payment processing for the sale is handled by the marketplace.