Any suggestions on finding a developer that can handle geodirectory?

I am hoping to find someone who can implement the following:

I have assigned categories by genre of food. I need to provide an average star rating for all restaurants in the Italian food category?

For example, Italian restaurant #1 has 5 stars and Italian restaurant #2 has 4 stars. I would like to display “Average Rating for all Italian Restaurants – 4.5 stars.”

From my understanding, this is how it is possible:

1) Refer best of widget code especially this function geodir_bestof_places_by_term. It can get the posts by term (i.e category)

2) Once you get the posts get the average rating of each listing. you can get overall individual rating using this function geodir_get_post_rating($post->ID);

3) Now all you have to do is add those individual ratings and divide by the number of listings.