diff --git a/crates/contracts/artifacts/Solver.json b/crates/contracts/artifacts/Solver.json
index e93eb9b7f2..5adf514a33 100644
--- a/crates/contracts/artifacts/Solver.json
+++ b/crates/contracts/artifacts/Solver.json
@@ -1 +1 @@
-{"abi":[{"inputs":[{"internalType":"address","name":"token","type":"address"},{"internalType":"address","name":"owner","type":"address"}],"name":"storeBalance","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"contract ISettlement","name":"settlementContract","type":"address"},{"internalType":"address payable","name":"trader","type":"address"},{"internalType":"address","name":"sellToken","type":"address"},{"internalType":"uint256","name":"sellAmount","type":"uint256"},{"internalType":"address","name":"nativeToken","type":"address"},{"internalType":"address payable","name":"receiver","type":"address"},{"internalType":"bytes","name":"settlementCall","type":"bytes"}],"name":"swap","outputs":[{"internalType":"uint256","name":"gasUsed","type":"uint256"},{"internalType":"uint256[]","name":"queriedBalances","type":"uint256[]"}],"stateMutability":"nonpayable","type":"function"}],"bytecode":"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","deployedBytecode":"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+{"abi":[{"inputs":[{"internalType":"address","name":"token","type":"address"},{"internalType":"address","name":"owner","type":"address"}],"name":"storeBalance","outputs":[],"stateMutability":"nonpayable","type":"function"},{"inputs":[{"internalType":"contract ISettlement","name":"settlementContract","type":"address"},{"internalType":"address payable","name":"trader","type":"address"},{"internalType":"address","name":"sellToken","type":"address"},{"internalType":"uint256","name":"sellAmount","type":"uint256"},{"internalType":"address","name":"buyToken","type":"address"},{"internalType":"address","name":"nativeToken","type":"address"},{"internalType":"address payable","name":"receiver","type":"address"},{"internalType":"bytes","name":"settlementCall","type":"bytes"}],"name":"swap","outputs":[{"internalType":"uint256","name":"gasUsed","type":"uint256"},{"internalType":"uint256[]","name":"queriedBalances","type":"uint256[]"}],"stateMutability":"nonpayable","type":"function"}],"bytecode":"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","deployedBytecode":"0x608060405234801561001057600080fd5b50600436106100365760003560e01c8063290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diff --git a/crates/contracts/solidity/Solver.sol b/crates/contracts/solidity/Solver.sol
index 495622a5d8..791da21f48 100644
--- a/crates/contracts/solidity/Solver.sol
+++ b/crates/contracts/solidity/Solver.sol
@@ -31,6 +31,7 @@ contract Solver {
     /// @param trader - address of the order owner doing the trade
     /// @param sellToken - address of the token being sold
     /// @param sellAmount - amount being sold
+    /// @param buyToken - address of the token being bought
     /// @param nativeToken - ERC20 version of the chain's token
     /// @param receiver - address receiving the bought tokens
     /// @param settlementCall - the calldata of the `settle()` call
@@ -42,6 +43,7 @@ contract Solver {
         address payable trader,
         address sellToken,
         uint256 sellAmount,
+        address buyToken,
         address nativeToken,
         address payable receiver,
         bytes calldata settlementCall
@@ -53,10 +55,14 @@ contract Solver {
         // Prepare the trade in the context of the trader so we are allowed
         // to set approvals and things like that.
         Trader(trader).prepareSwap(settlementContract, sellToken, sellAmount, nativeToken, receiver);
+        this.storeBalance(sellToken, address(settlementContract));
+        this.storeBalance(buyToken, address(settlementContract));
         uint256 gasStart = gasleft();
         // TODO can we assume the overhead of this function call to be negligible due to inlining?
         address(settlementContract).doCall(settlementCall);
         gasUsed = gasStart - gasleft() - _simulationOverhead;
+        this.storeBalance(sellToken, address(settlementContract));
+        this.storeBalance(buyToken, address(settlementContract));
         queriedBalances = _queriedBalances;
     }
 
@@ -72,9 +78,7 @@ contract Solver {
                 ? owner.balance
                 : IERC20(token).balanceOf(owner)
         );
-        // Account for costs of gas used outside of metered section. Noting that
-        // reading cold storage costs more which results in higher overhead for the first call
-        uint256 measurementOverhead = _queriedBalances.length == 1 ? 13355 : 4460;
-        _simulationOverhead += gasStart - gasleft() + measurementOverhead;
+        // Account for costs of gas used outside of metered section.
+        _simulationOverhead += gasStart - gasleft() + 4460;
     }
 }
diff --git a/crates/shared/src/price_estimation/trade_verifier.rs b/crates/shared/src/price_estimation/trade_verifier.rs
index 504be72b59..355120c9ce 100644
--- a/crates/shared/src/price_estimation/trade_verifier.rs
+++ b/crates/shared/src/price_estimation/trade_verifier.rs
@@ -22,7 +22,7 @@ use {
         order::{OrderData, OrderKind, BUY_ETH_ADDRESS},
         signature::{Signature, SigningScheme},
     },
-    number::nonzero::U256 as NonZeroU256,
+    number::{conversions::u256_to_big_int, nonzero::U256 as NonZeroU256},
     std::sync::Arc,
     web3::{ethabi::Token, types::CallRequest},
 };
@@ -127,6 +127,7 @@ impl TradeVerifying for TradeVerifier {
                 verification.from,
                 query.sell_token,
                 sell_amount,
+                query.buy_token,
                 self.native_token,
                 verification.receiver,
                 Bytes(settlement.data.unwrap().0),
@@ -176,18 +177,18 @@ impl TradeVerifying for TradeVerifier {
             .simulate(call, overrides, Some(block))
             .await
             .context("failed to simulate quote")?;
-        let summary =
-            SettleOutput::decode(&output).context("could not decode simulation output")?;
+        let summary = SettleOutput::decode(&output, query.kind)
+            .context("could not decode simulation output")?;
         let verified = VerifiedEstimate {
-            out_amount: summary
-                .out_amount(query.kind)
-                .context("could not compute out_amount")?,
+            out_amount: summary.out_amount,
             gas: summary.gas_used.as_u64(),
             solver: trade.solver,
         };
         tracing::debug!(
             out_diff = ?trade.out_amount.abs_diff(verified.out_amount),
             gas_diff = ?trade.gas_estimate.abs_diff(verified.gas),
+            lost_buy_amount = ?summary.buy_tokens_diff,
+            lost_sell_amount = ?summary.sell_tokens_diff,
             time = ?start.elapsed(),
             promised_out_amount = ?trade.out_amount,
             promised_gas = trade.gas_estimate,
@@ -306,39 +307,51 @@ fn add_balance_queries(
     settlement
 }
 
-/// Output of `Trader::settle` smart contract call.
+/// Analyzed output of `Solver::settle` smart contract call.
 #[derive(Debug)]
 struct SettleOutput {
     /// Gas used for the `settle()` call.
     gas_used: U256,
-    /// Balances queried during the simulation in the order specified during the
-    /// simulation set up.
-    queried_balances: Vec<U256>,
+    /// `out_amount` perceived by the trader (sell token for buy orders or buy
+    /// token for sell order)
+    out_amount: U256,
+    /// Difference in buy tokens of the settlement contract before and after the
+    /// trade.
+    buy_tokens_diff: num::BigInt,
+    /// Difference in sell tokens of the settlement contract before and after
+    /// the trade.
+    sell_tokens_diff: num::BigInt,
 }
 
 impl SettleOutput {
-    fn decode(output: &[u8]) -> Result<Self> {
+    fn decode(output: &[u8], kind: OrderKind) -> Result<Self> {
         let function = Solver::raw_contract().abi.function("swap").unwrap();
         let tokens = function.decode_output(output).context("decode")?;
-        let (gas_used, queried_balances) = Tokenize::from_token(Token::Tuple(tokens))?;
-        Ok(Self {
-            gas_used,
-            queried_balances,
-        })
-    }
+        let (gas_used, balances): (U256, Vec<U256>) = Tokenize::from_token(Token::Tuple(tokens))?;
+
+        let settlement_sell_balance_before = u256_to_big_int(&balances[0]);
+        let settlement_buy_balance_before = u256_to_big_int(&balances[1]);
+
+        let trader_balance_before = balances[2];
+        let trader_balance_after = balances[3];
+
+        let settlement_sell_balance_after = u256_to_big_int(&balances[4]);
+        let settlement_buy_balance_after = u256_to_big_int(&balances[5]);
 
-    /// Computes the actual [`Trade::out_amount`] based on the simulation.
-    fn out_amount(&self, kind: OrderKind) -> Result<U256> {
-        let balances = &self.queried_balances;
-        let balance_before = balances.first().context("no balance before settlement")?;
-        let balance_after = balances.get(1).context("no balance after settlement")?;
         let out_amount = match kind {
             // for sell orders we track the buy_token amount which increases during the settlement
-            OrderKind::Sell => balance_after.checked_sub(*balance_before),
+            OrderKind::Sell => trader_balance_after.checked_sub(trader_balance_before),
             // for buy orders we track the sell_token amount which decreases during the settlement
-            OrderKind::Buy => balance_before.checked_sub(*balance_after),
+            OrderKind::Buy => trader_balance_before.checked_sub(trader_balance_after),
         };
-        out_amount.context("underflow during out_amount computation")
+        let out_amount = out_amount.context("underflow during out_amount computation")?;
+
+        Ok(SettleOutput {
+            gas_used,
+            out_amount,
+            buy_tokens_diff: settlement_buy_balance_before - settlement_buy_balance_after,
+            sell_tokens_diff: settlement_sell_balance_before - settlement_sell_balance_after,
+        })
     }
 }