Upkeep for summoned units

[llamabeast]

I'd always assumed that summons were upkeep-free, and was cheerfully summoning lots of trolls, while bemoaning my inexplicably low net income. Then I saw on one of the far-too-fast-to-read hints that trolls demand lots of gold, so I did a test, and indeed they do (around 80 gold a turn for a sea king court - eek!). But I assumed it was just trolls. But I just read somewhere (Sunray's Dom2 page, in fact) that other summons, like black hawks, also cost upkeep. This is very bad news, as I'm pretty much King of the Black Hawks in one MP game at the moment.

So - is there any way to find out which units cost upkeep, and how much? Is there a list anywhere? Or do I have to keep on loading up a test game, summoning a unit and seeing how much my upkeep changes?

Thanks!

llamabeast