Opencart multi-vendor location search

We are looking for an opencart (and php) expert, who can write a location based search option for our multi-vendor plug-in. The location search will use the location of the (multi-) vendors and sort the listings based on the provided address by the user. We basically need the following features: • Search by Country/State/City • Distance & Radius Searching • Geo-location IP mapping: The IP location of the user will be the default location. Find my location will be integrated and will become a selection item within the location menu. • General Search and location search parts will be separated. General search will be there at all times. Location search will only be visible and used in location listings We look for: • We only consider developers with experience in developing opencart projects. Show me examples. • We need someone who is an expert in php and knows opencart extremely well to customize it to our needs. • This may turn to be a long term job, since we don’t like to change programmers much, if we work well together, other works are guaranteed. Besides this project, we have others to start working on soon. We do not respond to bids if you don't show you've read the description.