vPost does not offer you a parcel consolidation service. This does not allow to combine into one consolidated parcel.
vPost only offers aggregate service, which means you are allowed to pay one base charge per invoice instead of one base charge per package.
To utilize this feature, simply withhold payment till all the packages you want to pay for together are available to check out.
Please note that a holding fee will be applicable for packages that are held for more than 30 days.