if a record exists in the table, run a procedure

Question

I'm trying to run a procedure, once it finds a record in a table, in which, if you find the record, verifies that record type is another value stored in another column, if not found, save a data in a variable that is already declared.

IF Exists(SELECT *
FROM    [Roga].[dbo].[RFC_Empresa_Buzon_Fiscal]
WHERE RFC = @eRFC)
SELECT    TOP(1)
        RTRIM(LTRIM(REPLACE(RFC, ' ', '')))                AS    RFC,
        RTRIM(LTRIM(Tipo))                AS    Tipo,
        RTRIM(LTRIM(Razon_Social))    AS    Razon
FROM    [Roga].[dbo].[RFC_Empresa_Buzon_Fiscal]
WHERE    RTRIM(LTRIM(REPLACE(RFC, ' ', ''))) LIKE @eRFC
ELSE
SET
@eRFC = 'RFC No Valido'

This is what I wear, what I need is that the value of the "Tipo" column, is stored in a variable, which will use later to call it from C #, could guide me, I'm new to SQL Server.

Thank you