Be careful with Tough Tracks Travel, a car rental agency in Kenya.
We rented a Hilux double cab with roof top tent in 2006, which is excellent for game viewing and travelling. Tough tracks travel gives you a rate in british pounds by internet and offer, but when you take over the car in kenya, they debit your card in kenya shilling. That is nowhere mentioned before so be aware to know the exact exchange rate! We got the wrong exchange rate which was for sure to high and paid in the end about 250 USD to much (with the official rate given by barclays bank). Although emailed a couple of times, they told us to pay back one day which was charged to much: nothing happend, we did not get any money till now !
The car we had was also poor maintained, but its a toyota, what means reliable: we had a wonderful time in kenya, without any breakdown.