Adding more settings in search

Hi. I want to create more advanced search. Now I got with categories, but I want in each post as well add like category, but will be not, will be city or area. I gonna have maybe 10 areas. Then will be writing new post, like choosing category, as well I want to choose area. Whats the best and easiest way to make it? As well I want to add separate function in search, where visitors can search by category like now, as well by area. Help me please.