Definitely. Recycled kitchens 'r' us 
Get the units OUT of the garden, you only need a small amount of water to totally bugger'm up, trust me.
Understood - that chipboard loves to wick it up.
It's raining here a fair bit, but I've got two new tarps over it and so far everything has been OK. Because of the rain I've had some time off work to get on with it, we're not far off getting the rest in.
Despite the tarps some of the units seem to have a layer of water hanging off the bottoms of them - perhaps condensation making it's way through the ground sheet? So far no damage but we're well aware we're on limited time.
When we were younger and marginally better off we did the new kitchen thing, which works well because you know in advance where everything goes so can plan plumbing and wiring in advance before it arrives. But with buying one off of eBay, it really was a case of see what we've got and working around it, so sadly it has to be stored somewhere and with the three kids space is a bit limited so garden it was...