Review my wordpress e-commerce site and optimise my geolocation & search functions

My site is an online marketplace of caterers which allows users to order local food for their office lunch, meetings and staff parties directly.

THE MAIN JOB:

In theory, the user enters their postcode and up pops a list of local caterers who serve their area. This vendors list can be further refined by the day/time/budget/category

Alternatively, if they know exactly the type of caterer/vendor they want, they can use the quick links to find vendors that specialise in that area. Once again the list can be further refined by day/time/budget

The attempt that has been made so far is not quite accurate, however.

There are also a few minor changes needed such as:

Help to review my plugins/suggest new ones

To fix the pop-up box which is to show the quantity, drop-down, price, and a "special instructions" box outside of the "add to cart" button - as per www.trycaviar.com. Currently, only half the box is showing

Remove the hover effect on dishes which is part of the theme (where the background goes orange and the buttons appear); clicking anywhere on the picture of the dish should produce the same effect as clicking the "add to cart" button - which is to show the pop-up box; when the item is added to the cart, the pop-up box should be closed.

Add a 'budget' slider filter on the results pages

Fix Caterer registration to ensure location is saved correctly.

Reinstate the 'i' button next to the "Add to cart" buttons which link to the details pages.

Like caviar, there should be a very short description (the "cuisine style" field) underneath or next to the caterers name when they pop up in the results page from searches.

The link between thumbnail images and main page images for dishes has broken, and the slug can't be changed for existing dishes

When the client clicks add to cart, sometimes it creates an extra "checkout" button on some browsers: what should always happen is that the original add to cart button changes to "checkout"

The option for caterers to change their featured image from their dashboard needs reinstating

Please note this is a responsive theme.

PLEASE ADVISE ALSO HOW LONG THE JOB WILL TAKE - THANK YOU