Hi Kishore
If you are sure that your controlling area is going to have only one company code - Then choose Curr Type 10
You can add more companies in the Controlling area if it has Curr Type 10 - Provided all company codes have same currency
If you feel you may add some companies in the controlling area which may have a different currency, then nchoose Curr Type 20
Reports can be made to show both comp code currency amounts and trans curr amounts
Br. Ajay M