Is it possible to add option so the transaction(sell buy) and condition(new-used) of items are rquired? like phone location and name
most everything you want to need, is already inside Veronika, for example :
On the form you are required to add an email, I think if you want to add the same to Transaction, name, etc..you just have to replicate the configuration on email.
Just watch carefully and compare this :
<label for="phone"><?php _e('Mobile Phone', 'veronika'); ?></label>
whit this
<label for="contactEmail"><span><?php _e('E-mail', 'veronika'); ?></span><span class="req">*</span></label>
result ? .. what you need is "
<span class="req">*</span></label>
I am not an expert, but I apply this almost always, and I learn how things work