Dryvit over Cinderblock? Good idea? Expensive?

[Andrew S.]

I'm considering a property that is built with painted cinderblock. It was built in the 50-ies and there is little insulation (I doubt the blocks are filled with foam, etc). Some of the interior is drywalled but doesn't look like they put in a lot of insulation between the blocks and the sheetrock either. Other parts of the interior are just basically the (painted) cinderblock.

So, I'm thinking of adding a siding such as Dryvit in order to a.) improve insulation and b.) enhance the curb appeal.

Does anyone have advice as far as potential pitfalls and approximate cost of such a retrofit? This is a small 2/1 800-900 sqft one-story building.