Screenshot for reference: http://ScrnSht.com/qzzdqs
(the cutoff display is in question in another post: https://premium.wpmudev.org/forums/topic/classifieds-listings-cut-off-on-the-side-in-the-middle-of-the-content-area )
1) The entry field for amount should have a currency symbol to be selected at time of posting. Additionally, the Settings should allow for selecting the allowed currencies or to allow all currencies. For example, only USD$ can be posted. Or USD and EUR. Or any/all currencies.
2) Since there's a website link field, shouldn't it be turned into an HTML link if the field isn't empty? Please do that.
3) When someone clicks to "Contact User", the subject line should be the classified listing ID and/or title, not blank.