diff --git a/lib/bill-math.js b/lib/bill-math.js
index 8b143873..c94cc2fb 100644
--- a/lib/bill-math.js
+++ b/lib/bill-math.js
@@ -1,15 +1,112 @@
 const _ = require('lodash/fp')
 const sumService = require('@haensl/subset-sum')
 
-const getSolution = (units, amount) => {
-  const billList = _.reduce(
-    (acc, value) => {
-      acc.push(..._.times(_.constant(value.denomination), value.count))
-      return acc
-    },
-    [],
-    units
-  )
+const BILL_LIST_MODES = {
+  LAST_UNIT_FIRST: 0,
+  FIRST_UNIT_FIRST: 1,
+  LOWEST_VALUE_FIRST: 2,
+  HIGHEST_VALUE_FIRST: 3,
+  UNIT_ROUND_ROBIN: 4,
+  VALUE_ROUND_ROBIN: 5
+}
+
+const buildBillList = (units, mode) => {
+  switch (mode) {
+    case BILL_LIST_MODES.LAST_UNIT_FIRST:
+      return _.reduce(
+        (acc, value) => {
+          acc.push(..._.times(_.constant(value.denomination), value.count))
+          return acc
+        },
+        [],
+        _.reverse(units)
+      )
+    case BILL_LIST_MODES.FIRST_UNIT_FIRST:
+      return _.reduce(
+        (acc, value) => {
+          acc.push(..._.times(_.constant(value.denomination), value.count))
+          return acc
+        },
+        [],
+        units
+      )
+    case BILL_LIST_MODES.LOWEST_VALUE_FIRST:
+      return _.reduce(
+        (acc, value) => {
+          acc.push(..._.times(_.constant(value.denomination), value.count))
+          return acc
+        },
+        [],
+        _.orderBy(['denomination'], ['asc'])(units)
+      )
+    case BILL_LIST_MODES.HIGHEST_VALUE_FIRST:
+      return _.reduce(
+        (acc, value) => {
+          acc.push(..._.times(_.constant(value.denomination), value.count))
+          return acc
+        },
+        [],
+        _.orderBy(['denomination'], ['desc'])(units)
+      )
+    case BILL_LIST_MODES.UNIT_ROUND_ROBIN:
+      {
+        const amountOfBills = _.reduce(
+          (acc, value) => acc + value.count,
+          0,
+          units
+        )
+      
+        const _units = _.cloneDeep(units)
+        const bills = []
+      
+        for(let i = 0; i < amountOfBills; i++) {
+          const idx = i % _.size(_units)
+          if (_units[idx].count > 0) {
+            bills.push(_units[idx].denomination)
+          }
+      
+          _units[idx].count--
+      
+          if (_units[idx].count === 0) {
+            _units.splice(idx, 1)
+          }
+        }
+
+        return bills
+      }
+    case BILL_LIST_MODES.VALUE_ROUND_ROBIN:
+      {
+        const amountOfBills = _.reduce(
+          (acc, value) => acc + value.count,
+          0,
+          units
+        )
+      
+        const _units = _.orderBy(['denomination'], ['asc'])(_.cloneDeep(units))
+        const bills = []
+      
+        for(let i = 0; i < amountOfBills; i++) {
+          const idx = i % _.size(_units)
+          if (_units[idx].count > 0) {
+            bills.push(_units[idx].denomination)
+          }
+      
+          _units[idx].count--
+      
+          if (_units[idx].count === 0) {
+            _units.splice(idx, 1)
+          }
+        }
+
+        return bills
+      }
+    default:
+      throw new Error(`Invalid mode: ${mode}`)
+  }
+}
+
+const getSolution = (units, amount, mode) => {
+  const billList = buildBillList(units, mode)
   
   const solver = sumService.subsetSum(billList, amount.toNumber())
   const solution = _.countBy(Math.floor, solver.next().value)
@@ -39,7 +136,7 @@ const solutionToOriginalUnits = (solution, units) => {
 }
 
 function makeChange(outCassettes, amount) {
-  const solution = getSolution(outCassettes, amount)
+  const solution = getSolution(outCassettes, amount, BILL_LIST_MODES.VALUE_ROUND_ROBIN)
   return solutionToOriginalUnits(solution, outCassettes)
 }
 
diff --git a/lib/graphql/resolvers.js b/lib/graphql/resolvers.js
index 984e090b..ea7100bc 100644
--- a/lib/graphql/resolvers.js
+++ b/lib/graphql/resolvers.js
@@ -5,6 +5,7 @@ const plugins = require('../plugins')
 const configManager = require('../new-config-manager')
 const { batchGetCustomInfoRequest, getCustomInfoRequests } = require('../new-admin/services/customInfoRequests')
 const state = require('../middlewares/state')
+const { getMachine } = require('../machine-loader')
 
 const VERSION = require('../../package.json').version
 
@@ -114,6 +115,7 @@ const staticConfig = ({ currentConfigVersion, deviceId, deviceName, pq, settings
     configManager.getOperatorInfo(settings.config),
     configManager.getReceipt(settings.config),
     !!configManager.getCashOut(deviceId, settings.config).active,
+    getMachine(deviceId, currentConfigVersion),
   ])
     .then(([
       enablePaperWalletOnly,
@@ -124,6 +126,7 @@ const staticConfig = ({ currentConfigVersion, deviceId, deviceName, pq, settings
       operatorInfo,
       receiptInfo,
       twoWayMode,
+      { numberOfCassettes, numberOfStackers },
     ]) =>
       (currentConfigVersion && currentConfigVersion >= staticConf.configVersion) ?
       null :
@@ -138,7 +141,7 @@ const staticConfig = ({ currentConfigVersion, deviceId, deviceName, pq, settings
             languages: localeInfo.languages,
             fiatCode: localeInfo.fiatCurrency
           },
-          machineInfo: { deviceId, deviceName },
+          machineInfo: { deviceId, deviceName, numberOfCassettes, numberOfStackers },
           twoWayMode,
           speedtestFiles,
           urlsToPing,
diff --git a/lib/graphql/types.js b/lib/graphql/types.js
index 5c96df82..2de2b338 100644
--- a/lib/graphql/types.js
+++ b/lib/graphql/types.js
@@ -30,6 +30,8 @@ type OperatorInfo {
 type MachineInfo {
   deviceId: String!
   deviceName: String
+  numberOfCassettes: Int
+  numberOfStackers: Int
 }
 
 type ReceiptInfo {
diff --git a/new-lamassu-admin/src/pages/Machines/MachineComponents/Cassettes/Cassettes.js b/new-lamassu-admin/src/pages/Machines/MachineComponents/Cassettes/Cassettes.js
index 23ad89ab..d14db761 100644
--- a/new-lamassu-admin/src/pages/Machines/MachineComponents/Cassettes/Cassettes.js
+++ b/new-lamassu-admin/src/pages/Machines/MachineComponents/Cassettes/Cassettes.js
@@ -56,7 +56,7 @@ const ValidationSchema = Yup.object().shape({
     .required('Required')
     .integer()
     .min(0)
-    .max(60),
+    .max(40),
   stacker1r: Yup.number()
     .label('Stacker 1R')
     .required('Required')
diff --git a/new-lamassu-admin/src/pages/Maintenance/Wizard/Wizard.js b/new-lamassu-admin/src/pages/Maintenance/Wizard/Wizard.js
index 2c26fda4..a57151c8 100644
--- a/new-lamassu-admin/src/pages/Maintenance/Wizard/Wizard.js
+++ b/new-lamassu-admin/src/pages/Maintenance/Wizard/Wizard.js
@@ -129,10 +129,21 @@ const Wizard = ({ machine, cashoutSettings, locale, onClose, save, error }) => {
             .required()
             .min(0)
             .max(
-              cashUnitCapacity[machine.model].stacker,
-              `${modelPrettifier[machine.model]} maximum stacker capacity is ${
-                cashUnitCapacity[machine.model].stacker
-              } bills`
+              i === 1
+                ? cashUnitCapacity[machine.model].stacker -
+                    cashUnitCapacity[machine.model].escrow
+                : cashUnitCapacity[machine.model].stacker,
+              i === 1
+                ? `${
+                    modelPrettifier[machine.model]
+                  } maximum stacker capacity for the escrow unit is ${cashUnitCapacity[
+                    machine.model
+                  ].stacker - cashUnitCapacity[machine.model].escrow} bills`
+                : `${
+                    modelPrettifier[machine.model]
+                  } maximum stacker capacity is ${
+                    cashUnitCapacity[machine.model].stacker
+                  } bills`
             )
         })
       },
diff --git a/new-lamassu-admin/src/pages/Maintenance/helper.js b/new-lamassu-admin/src/pages/Maintenance/helper.js
index 3074ca39..1a3f11c2 100644
--- a/new-lamassu-admin/src/pages/Maintenance/helper.js
+++ b/new-lamassu-admin/src/pages/Maintenance/helper.js
@@ -166,7 +166,12 @@ const getElements = (
               denomination={getCashoutSettings(id)?.[`stacker${it}f`]}
               currency={{ code: fiatCurrency }}
               notes={cashUnits[`stacker${it}f`]}
-              capacity={cashUnitCapacity[model].stacker}
+              capacity={
+                it === 1
+                  ? cashUnitCapacity[model].stacker -
+                    cashUnitCapacity[model].escrow
+                  : cashUnitCapacity[model].stacker
+              }
               width={
                 widthsByCashUnits[getMaxNumberOfCashUnits(machines)]?.unitGraph
               }
diff --git a/new-lamassu-admin/src/utils/machine.js b/new-lamassu-admin/src/utils/machine.js
index 42a19490..4684e5ac 100644
--- a/new-lamassu-admin/src/utils/machine.js
+++ b/new-lamassu-admin/src/utils/machine.js
@@ -15,6 +15,7 @@ const cashUnitCapacity = {
   aveiro: {
     cashbox: 1500,
     stacker: 60,
+    escrow: 20,
     cassette: 500
   },
   tejo: {