manual calculatin of the RAND function

Please verify:
1) Column C is checked from row 6 down. (Macro can find the bottom each time it runs.)
2) Each "buy" or "sell" in column C gets a code in column A. (Are there any other entry types in column C?)
3) Codes start with a set number (Note- Stored in a cell? or in macro itself? or as Defined Name in Name Manager?)
4) Starting from top, each new code adds 1-300 to previous value.