This is one of the most enjoyable and rewarding things I have done since ppl. You need 70hrs P1 as per the previous post. I did this after 3 years post PPl with approx 300hrs, IMC and approx 120 hrs in the arrow.
Really hones up your flying skills and I think worth getting experience with a complex single first.
It is however great fun and twin flying always broadens the smile further.
Be aware that hiring a twin post MER is not easy. Many will insist on high numbers of P1 multi hours (understandably) and may need to look at shares.
It is an experience though not to be missed.