1. Yes, you can edit the field values for the "State" field from within the ClassiPress admin dashboard. By default these are filled in with US States, but again, easily changed as is the actual field name "State".
2. Yes, you can change ad pricing at any time so once the setting is changed it will effect further ads posted on the site. Just a sidenote of this, if you choose to use the renew ad option, ads will only be renewed based on the original terms of the ad. i.e. if the ad was originally listed for free, it won't change to a paid relist.
3. The payment gateway used in ClassiPress, PayPal, does not currently support Indian Rupees, so technically the option to charge in this currency is not available (you can charge in any currencies listed, as seen on the
ClassiPress admin demo). You can however allow ad listings in the currency of your choice, and note there is also a bank transfer option.
4. You could create a custom field with dropdown options/radio buttons if you wished to do so.
5. Currently only by entering in the location into the search itself. There are plans for an advanced search functionality in the next release of the theme (
v3.1).