Analyze Excel Files & Create an Excel Spreedsheet for Accounting using a Macro or a Plugin

I am a small business owner trying to calculate my sales figures and tax amounts for taxation reporting purposes from a set of Excel files that I have used as Invoices for my clients. This can be a rather straightforward Macro or a third party plugin that can be used to Analyze a set of Excel 2010 /2016 documents with a single worksheet in each. I have a standard Tax Invoice template in Excel which has details of my client , date of invoice , invoice number and the details of services and equipment supplied , pre tax amounts, GST amount and Total Invoice Amount. I have close to 150 separate files (invoices) generated using the same template baring a few changes in the logo . The data that needs to be extracted is more or less in the same fields from each file. All I want to do is to have a brand new interactive Excel sheet to provide or feed in the file names ( location on a local hard drive ) or a directory containing all the Excel files. Your macro should be able to open each file, extract the specific data and spit it into a new combined document with the respective column headings. I would like to analyse the data in this final spreadsheet on the basis of Date/Month/Year/ Client. I have attached a sample spreadsheet invoice here. The data that needs to be extracted is in RED. Additionally I will pay a bonus if I could :- 1) Edit the main template to add a second worksheet called Costs going forward and put in the costs for any Hardware or Software invoiced and get that reported as well to arrive at a rough profit or loss statement 2) Extract additional Data from the same worksheet(s)which is not in the same cell under the sub headings - Hardware Supplied , Services Rendered , Software & Subscriptions , Travel etc. Ideally I should be able to specify the string of the sub heading to be able to extract the data. I need this done in the next 72 hours. If you require me to install a plugin as part of your solution, please provide clear and concise instructions. You are more than welcome to use any freely available Excel plugins. If there is a license fee to be paid please include that in your fee. Thanks and all the best. Please feel free to contact me for any further explanations. Cheers MD