Display cell as DATE and/or NUMBER format

I need help making my excel cell display as either DATE (10/11/12) or NUMBER (1234) format depending on my cell reference (vlookup). Formatting cell as NUMBER, DATE or GENERAL cannot work because it will fixed number to date format or date to number format.

Example: when search “City Hall”, column A will be Date, column B will be sales. When search “Raffles Place”, column A will be number of people, column B will be name.

Is it even possible to do above with reference cell?