Building Cost Controll App

The App is to control all building costs on a many building sites. Each Building site to have its own Reference Job Name and Number The cost are for various Contractors and sub-contractors, e.g. Electricians and or Plasterers and or Plumbers, they provide their quote and we put our mark-up onto their price say 10% = $3500.00 + 10% = $3850.00 this % will be set for each Contractor or sub-contractor in two column's. We use a data base built in Access every day and would like to be able to do the same on a mobile phone. This App could talk to the Access Data base or stand alone. Please don't quote if you don't understand data-bases Thanks Farrel from Sydney