Raila is also in business. The summit brings together CEOs, Chairmen of companies etc. He has the right to be there in so many ways. As a former Prime Minister and senior politician, he is well placed to discuss the state of politics in Africa/Kenya and it's effect to business which I believe is one of the things that will be discussed at the summit. As to whether what he will say reflects the reality on the ground is another story! The only question is the capacity in which he's attending the summit.
Never count on making a good sale. Have the purchase price be so attractive that even a mediocre sale gives good returns.