Amount $0 on order summery page.
My Code for Buy Now Button is
<form action="https://www.paypal.com/cgi-bin/webscr" method="post" target="_top">
<input type="hidden" name="cmd" value="_s-xclick">
<input type="hidden" name="hosted_button_id" value="AF">
<input type="hidden" name="amount" value="10.10">
<table>
<tr><td><input type="hidden" name="on0" value="License Option">License Option</td></tr><tr><td><select name="os0">
<option value="Single User">Single User </option>
<option value="Site License">Site License </option>
<option value="Global License">Global License </option>
</select> </td></tr>
</table>
<input type="image" src="https://www.paypalobjects.com/en_GB/i/btn/btn_buynowCC_LG.gif" border="0" name="submit" alt="PayPal – The safer, easier way to pay online.">
<img alt="" border="0" src="https://www.paypalobjects.com/en_GB/i/scr/pixel.gif" width="1" height="1">
</form>
If you are trying to create button in your PayPal account, please do not change the name and value fields generated there. All data are saved in PayPal system and could not be modified in code line. If you are trying to create a customized button, please refer to below page for its details.