diff --git a/chain/actors/actor_miner.go b/chain/actors/actor_miner.go
index ff110da4d..e353069e3 100644
--- a/chain/actors/actor_miner.go
+++ b/chain/actors/actor_miner.go
@@ -19,6 +19,9 @@ func init() {
 	cbor.RegisterCborType(CommitSectorParams{})
 	cbor.RegisterCborType(MinerInfo{})
 	cbor.RegisterCborType(SubmitPoStParams{})
+	cbor.RegisterCborType(StorageVoucherData{})
+	cbor.RegisterCborType(StoragePaymentVerifyProof{})
+	cbor.RegisterCborType(PaymentVerifyParams{})
 }
 
 var ProvingPeriodDuration = uint64(2 * 60) // an hour, for now
diff --git a/chain/deals/client.go b/chain/deals/client.go
index 2b59af99e..46a8cd01a 100644
--- a/chain/deals/client.go
+++ b/chain/deals/client.go
@@ -196,18 +196,25 @@ type ClientDealProposal struct {
 	MinerID       peer.ID
 }
 
-func (c *Client) Start(ctx context.Context, p ClientDealProposal) (cid.Cid, error) {
-	commP, size, err := c.commP(ctx, p.Data)
+func (c *Client) VerifyParams(ctx context.Context, data cid.Cid) (*actors.StorageVoucherData, error) {
+	commP, size, err := c.commP(ctx, data)
 	if err != nil {
-		return cid.Undef, err
+		return nil, err
 	}
 
+	return &actors.StorageVoucherData{
+		CommP:     commP,
+		PieceSize: types.NewInt(uint64(size)),
+	}, nil
+}
+
+func (c *Client) Start(ctx context.Context, p ClientDealProposal, vd *actors.StorageVoucherData) (cid.Cid, error) {
 	// TODO: use data
 	proposal := StorageDealProposal{
 		PieceRef:          p.Data.String(),
 		SerializationMode: SerializationUnixFs,
-		CommP:             commP[:],
-		Size:              uint64(size),
+		CommP:             vd.CommP[:],
+		Size:              vd.PieceSize.Uint64(),
 		TotalPrice:        p.TotalPrice,
 		Duration:          p.Duration,
 		Payment:           p.Payment,
diff --git a/node/impl/full.go b/node/impl/full.go
index d578b878a..93488f006 100644
--- a/node/impl/full.go
+++ b/node/impl/full.go
@@ -69,6 +69,16 @@ func (a *FullNodeAPI) ClientStartDeal(ctx context.Context, data cid.Cid, miner a
 		return nil, err
 	}
 
+	vd, err := a.DealClient.VerifyParams(ctx, data)
+	if err != nil {
+		return nil, err
+	}
+
+	voucherData, err := cbor.DumpObject(vd)
+	if err != nil {
+		return nil, err
+	}
+
 	// setup payments
 	total := types.BigMul(price, types.NewInt(blocksDuration))
 
@@ -77,7 +87,20 @@ func (a *FullNodeAPI) ClientStartDeal(ctx context.Context, data cid.Cid, miner a
 	if err != nil {
 		return nil, err
 	}
-	sv, err := a.PaychVoucherCreate(ctx, paych, total, 0)
+
+	voucher := types.SignedVoucher{
+		// TimeLock:       0, // TODO: do we want to use this somehow?
+		Extra: &types.ModVerifyParams{
+			Actor:  miner,
+			Method: actors.MAMethods.PaymentVerify,
+			Data:   voucherData,
+		},
+		Lane:           0,
+		Amount:         total,
+		MinCloseHeight: blocksDuration, // TODO: some way to start this after initial piece inclusion by actor? (also, at least add current height)
+	}
+
+	sv, err := a.paychVoucherCreate(ctx, paych, voucher)
 	if err != nil {
 		return nil, err
 	}
@@ -97,7 +120,7 @@ func (a *FullNodeAPI) ClientStartDeal(ctx context.Context, data cid.Cid, miner a
 		MinerID:       pid,
 	}
 
-	c, err := a.DealClient.Start(ctx, proposal)
+	c, err := a.DealClient.Start(ctx, proposal, vd)
 	return &c, err
 }
 
@@ -584,21 +607,22 @@ func (a *FullNodeAPI) PaychVoucherAdd(ctx context.Context, ch address.Address, s
 // actual additional value of this voucher will only be the difference between
 // the two.
 func (a *FullNodeAPI) PaychVoucherCreate(ctx context.Context, pch address.Address, amt types.BigInt, lane uint64) (*types.SignedVoucher, error) {
+	return a.paychVoucherCreate(ctx, pch, types.SignedVoucher{Amount: amt, Lane: lane})
+}
+
+func (a *FullNodeAPI) paychVoucherCreate(ctx context.Context, pch address.Address, voucher types.SignedVoucher) (*types.SignedVoucher, error) {
 	ci, err := a.PaychMgr.GetChannelInfo(pch)
 	if err != nil {
 		return nil, err
 	}
 
-	nonce, err := a.PaychMgr.NextNonceForLane(ctx, pch, lane)
+	nonce, err := a.PaychMgr.NextNonceForLane(ctx, pch, voucher.Lane)
 	if err != nil {
 		return nil, err
 	}
 
-	sv := &types.SignedVoucher{
-		Lane:   lane,
-		Nonce:  nonce,
-		Amount: amt,
-	}
+	sv := &voucher
+	sv.Nonce = nonce
 
 	vb, err := sv.SigningBytes()
 	if err != nil {