This is worth investigating when you instruct an Insolvency Practitioner to begin setting up the Individual Voluntary Arrangement for you.
With a reputable firm, if the IVA is rejected, for example at the Meeting of Creditors and it IS NOT your fault, that is it is out of your control entirely, they will usually refund any money paid into the IVA, however if it was your fault, for example you gave false information about your circumstances and this came to light, you would normally lose any money paid into the IVA for the Insolvency Practitioner to recover their costs.