My aim is to add a calibration service for most, but not all of the products we sell.
There will be 3-5 options depending on the product.
Some of the options have an additional cost, some are FREE.
Having looked at 'Product Attributes', Custom Options and Configurable Products, it seems that the 'Custom Options' is the way to go with this.
I have around 1300 products and feel that adding the Custom Options for each of my products individually, would be very time consuming.
Could someone confirm my thoughts on using the Custom Options for this task and is there an easier (quicker) way to achieve my aim?
Thank you all in advance.
Custom options are easier than Configurable products, but with them you will not be able to track stock of your variations.
If you need some method to massively add them to products, default Magento does not allow to import them or copy and paste from one product to another. It is possible to achieve using extension (there are multiple).
One of them Store Manager for Magento. You can do it with 2-week free version that you can download from the link in my signature. It allows to copy-paste custom options and export/import them.
Here is tutorial -