In cases where you’re asking how many GB’s can be uploaded, I’d say it might be best to choose a system that is more of a repository solution for this number of images. I wouldn’t turn to Coda for image storage, I would use it when you need to add or accentuate data with images.
The images themselves won’t make the doc too much bigger, other than the code it requires to reference that image, but the image itself is not stored in with the doc. So any performance impact you might see is simply from the doc needing to pull the image in for display just like any webpage would be displaying images.
Again, if you’re talking 500 images per month, I might look to an image storage solution like Google Photos or Dropbox and then link to folders there. I know there are use-cases that benefit from having the images in Coda, this is just a thought experiment to entertain and to make sure you’re not trying to use Coda simply for image storage.
We’re still working out the numbers for limits, so not really sure just yet. We’ll know more as we start rolling out the file attachments feature.