Customization of Wordpress Theme

Hi! I'm currently looking for someone to customize the search/google maps of my wordpress site. I am building a directory website (with the MyListing theme [login to view URL]) for service providers that can also offer house calls but only within a certain radius of their actual address. Currently, in the MyListing theme the process looks like this: 1) The service provider can register with one (office) address. 2) Users (those who want to hire a service provider) of the site can then search for a service provider by zip code/city and also within a certain radius of that zip code/radius. 3) The results page (called "explore page") lists all the service providers whose address falls within that search criteria (meaning, their adress equals the zip code/city or is within the radius they were searching for) and also shows them tagged on a google map What I would need now is the following: 1) A service provider can register with one address + add a radius in which he offers house calls (so let’s say 50miles) 2) Users of the page can then search for a service provider by zip code/city and also within a certain radius of that zip code/city. 3) Results page lists all the service providers whose address falls within that search criteria (meaning, their adress equals the zip code/city or is within the radius they were searching for) AND all service providers whose „house call radius“ crosses with that search criteria (and therefore also falls within that search criteria). The service providers who only offer a housecall withing that radius wouldn't show up as a tag on the google map (because it's not a fix address) but I want them to show up in the search results. I was told it's quite a complex customization with lots of mathematical functions but I'm not giving up hope. :) Please send me a quote. If you can think of an easier way to achieve the same result feel free to let me know. Currently listing fields (like address, description, pictures etc.) can be shown/hidden based on the listing package. Ideally adding the radius would also be a listing field that can be shown/hidden basen on listing package so that only those who have bought the premium package for example can add their radius instead of only the address. Thank you & looking forward to hearing from you! Christina