For wooden sidings I've found a free photoscanned asset with texture. It's kinda high poly (expected) but it looks very good. You can always detach the 4 planks like I did and scatter them around to make it less repetitive. I used it with corona and unreal and it looks pretty nice.
www.remnantstudios.com/scans/pick-a-siding I ended making my own texture though because this one isn't very flexible. By the way there are a lot of free photoscanned assets on the site, worth bookmarking!
Actual 3d asset :

On a side note,
I've used parallax occlusion mapping a few times but with real-time engines. I Wonder if that technique would work (or would be beneficial) with offline renderers. I know parallax does not introduce new geometry, it's all in the shader. But it can look pretty damn good imo.
This travertine use this technique : (not my project)
