Create 3 Permits.
- Hot Work Permit / Confined Space Permit
- Planned Cost less than 100 $
- Planned Cost is 101 to 200 $
For 2 & 3rd Permits, assign classification values according to the requirement.
Using Authorisation, you can control the Permit release.
Check the below document.
http://scn.sap.com/community/eam/blog/2012/12/07/usage-of-permits-in-sap-plant-maintenance