context.BindValueTypeProperty(e => e.Type).To(lkpType).SetConvert(i => (int)i.Source).SetConvertBack(i => (VehicleRemainingDocumentType)i.Target);
context.BindValueTypeProperty(c => c.TransportationType).To(transportationTypeLookup).SetConvert(t => ((int)t.Source) == 0 ? null : (int?)t.Source);