> Plus, last time I checked you need to pay to be able to have proper access to all developer information
You checked wrong. Developer docs for production versions of Mac OS and iOS are all available for free with Xcode. You only need to pay for membership to the developer program, which gets you access to prerelease OSes (and related documentation), and lets you distribute your applications through the App Stores.
Mac cost perhaps a grand five years ago, still running fine. So about $200 a year. Meanwhile cheaper laptops I have used die a quicker death as they are not built as well, apparently. So my guess is that they are roughly equivalent.