Hi ViGotz ,
If these costs were not covered by your employer, I think you could claim the full deduction. Since the deductible amount is plausible, the tax office may not require evidence from you to confirm you did actually spend this amount.
In any case, I strongly recommend you to keep all receipts, evidence, documents, etc. in the future which are or might be relevant for your tax declaration.
If your employer did not cover the transport costs and the amount of costs is plausible, the tax office will probably accept them. However next time try to safe all the receipt you may need for the tax return.
Regards,
WilliamZ
