Can my techs purchase from vendors that have not been approved and added by the office staff?
Not directly, no. However, you could create a "placeholder" vendor in PartsLedger (e.g. "Miscellaneous Vendor" or "New Vendor") which the tech could select during the creation of a Purchase Order. Then, the tech could manually write the vendor's information in the PO description field.
Can I use my own ticket numbers instead of the ServiceTrade job number for work orders?
No, creating a ServiceTrade job will automatically create a Work Order in PartsLedger, which ties the Work Order to the Purchase Order that is created in the field by the tech.