Develop Iphone/Ipad App

Iam a motorhome owner and access to fresh water (tap) and ability to empty waste water while travelling around the UK is essential. Iam collating locations/addresses/post codes where people live which are willing to offer these two facilities. I want an app developing which will allow the user to locate nearby places or search by location, and pin point places which offer one or both of these facilities. I need the ability to edit the locations, add and delete as necessary. so basically two buttons, one for searching places which would allow a search by location within a search radius changeable in miles and the other button for places nearby which would give a visual of the uk map, pin point where you are currently and pins dotted around of the places (again with a search radius in miles) like a sliding bar.