VB Compare 4 Columns of Info with multiple data points then highlight - excel

Question

ColumnsExample
I'm trying to compare four columns for information. First Matching Location 1 data to Location 2 data, then comparing the Rented out Columns.
If Location 2 Rented Out Column D (for a specific car that matches column A with Column C) is greater than Rented out Column B then highlight cell (column D) yellow. Also if Rented out Column D
An example pic (ColumnsExample above) would be Honda and Dodge Rented out Column D would be highlighted for failing this.
I'm assuming I'll have to assign Daily, Weekly and Monthly a number value to compare against. Just not sure where to start!
Dim Alert As Range
Dim Daily, Weekly, Monthly As Integer
Set Daily = 1
Set Weekly = 2
Set Monthly = 3
Set ws = ActiveSheet
Set w = ws.Rows(1).Find("Rented Out 2", lookat:=xlWhole)
If Not w Is Nothing Then
For Each Alert In ws.Range(w, ws.Cells(Rows.Count,
w.Column).End(xlUp)).Cells
If Alert <= "Daily" Then
'Not sure how I can set this condition based on matching
'Location 1 with location 2 as well as Rented1 out vs
'Rented out 2
Alert.Interior.Color = 65535
End If
Next Alert
End If

Answer 1

Use a Dictionary for the comparison and a Function for the converting the strings to numbers.
Option Explicit
Sub MyMacro()
Dim ws As Worksheet, iLastRow As Long, r As Long
Dim dict As Object, key As String, s As String
Dim i As Integer
Set dict = CreateObject("Scripting.Dictionary")
Set ws = ActiveSheet
' scan col A & B
iLastRow = ws.Cells(Rows.Count, "A").End(xlUp).Row
For r = 2 To iLastRow
key = Trim(ws.Cells(r, "A"))
If Len(key) > 0 Then
s = Trim(ws.Cells(r, "B"))
i = TextToNo(s) ' convert text to number
If i = 0 Then
MsgBox "ERROR col B = '" & s & "'", vbCritical, "Row = " & r
Exit Sub
End If
' add to dictionery
If dict.exists(key) Then
MsgBox "ERROR col A duplicate key = '" & key & "'", vbCritical, "Row = " & r
Exit Sub
Else
dict.Add key, i
End If
End If
Next
' scan col C & D
iLastRow = ws.Cells(Rows.Count, "C").End(xlUp).Row
For r = 2 To iLastRow
key = Trim(ws.Cells(r, "C"))
If Len(key) > 0 Then
If dict.exists(key) Then
s = Trim(ws.Cells(r, "D"))
i = TextToNo(s)
If i = 0 Then
MsgBox "ERROR col D = '" & s & "'", vbCritical, "Row = " & r
Exit Sub
End If
' compare col D with col B
If i > dict(key) Then
ws.Cells(r, "D").Interior.Color = vbYellow
Else
ws.Cells(r, "D").Interior.Color = vbWhite
End If
End If
End If
Next
MsgBox "Finished"
End Sub
Function TextToNo(s As String) As Integer
Select Case LCase(s)
Case "daily": TextToNo = 1
Case "weekly": TextToNo = 2
Case "monthly": TextToNo = 3
Case Else: TextToNo = 0
End Select
End Function