We heard this question again from another developer and wanted to remind our community that eCheck.Net is enabled for all sandbox accounts but with low transaction limits: $100 per transaction and $5000.00 monthly.  These limits in the sandbox are arbitrary and allow developers to easily test a sucessful transaction (within limits), or decline (above limits).

You can always send a request to raise these limits. If you don’t, it will give you a straight decline if you try to run a transaction that is more than your transaction size limit.

Richard