How to give a range or List option in Validation/Substitution

Hi,

I am not aware of of giving a list option or range option while defining a Validation or substitution.

For example:

1. <b><u>List:</u></b> I want the pre-requisite to check Company Code = a constant value say 1000 but it should check only for few selected document types like KR, RE, SA, RV etc.

2.<u><b> Range</b></u> : It should check only for vendors between range 100000 to 999999.

So what needs to be done for meeting my these requirements.

Plz suggest.

Points will be suitable rewarded for replies.

regards

AVM