I renewed my IR abroad recently, and the discussion arose about "single pilot" 800m RVR minima. UK IRE told me - it applies in all countries, as far as he knew. Spanish and Austrian IREs told me - never heard of that - must be a UK thing, OR, it must only be for commercial ops, not private.
The other thing I asked about was the expression "single pilot". Does it mean (a) it would be OK to go down to the published RVR minima if we have two IR pilots up front in the C172, or (b) it only applies to AIRCRAFT that are certified for single crew ops. The last I heard, the answer is (b). However, the expression "single pilot" is ambiguous, and open to misinterpretation - beware.