Hi, there's a mistake in the way you think it works. The Blender Advanced software is actually a template allowing you to make renders with advanced features. So, you import the build in Blender (by exporting it on Mecabricks) and the template will allow you to configure the settings of the render. If you used the Blender lite template earlier, then it's easy to say that it works the same way but with more features. https://www.mecabricks.com/en/shop/product/4

So, the Blender Advanced template is unrelated to the online Render service. If you start to learn Blender (and buy the Blender advanced template)... You'll be able to tweak the resolution, have unlimited size limit, no watermark (unless you add it yourself) and there's no limit on renders a day. But there's a limit on the number of exports you can do a day. You own full control of how the render is going to look if you take the time to configure the render. After all, the Blender advanced plugin has been made to make configuration easier and faster. Later on, the online render service came to make it even more easier for users to get started with it.

I'm not entirely sure if the same options are present in the Blender Advanced template, but I do think so.

With the Blender add-on you have full control over your render. No limitations whatsoever as everything is happening on your computer. Try the free add-on first and if you can make it work you will have no issues with the pay version. Only more options.

The online rendering service is different as all the computation is made on servers I built myself. On the other hand it is way faster than your home computer and no special skills are required.