Changes to an existing extension

I have recently had an extension developed to my opencart website - the developer is away for about 10 days but I have some urgent changes to add to it now. It allows me to enter a cost price, add a markup calculation and tax (if paid) on the cost price to calculate and save the new sale price. This extension is working fine but I need a few changes made to it. The changes are listed below:

1. A bulk update option. This bulk option needs to allow me to select products or product categories (select all, select singles or select none - options). This bulk update will allow me to select a group of products or all products in selected categories and apply the new markup options with one click. This page also needs to have a button to update all tax rates of cost prices with one click (so if the vat rate changes i can update it all - vat rate is already set separately in admin from the default tax in opencart)

2. Make this extension compatible with the CSV import/export feature extension that I have on the site too so it imports/exports the new fields (cost, markup, tax)

3. Make the extension work with another extension that allows me to click text fields (like price) from the admin product list to edit a field directly from the product listing page.

4. I want the existing tick box that adds tax to the cost price to be replaced with 'do not add tax' so that by default it does add tax unless I select not to.

The previous developer was going to do these changes for $20 because they're simple changes so please bid appropriately. Please note the extension exists and is working right just need the changes done for it.

HTML MySQL Open Cart PHP

Project ID: #4830406

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