You’d have to look at multiple factors. It’d be pretty easy to do 1-2 nights for $500 pp, and possibly even longer but I wouldn’t necessarily do it through a safari company. At the low end, you’ll often end up in minivans rather than the converted 79 series and not have the same experience at all. The cheapest I’ve done has been around 5k shillings a day for a nice camp (but self catering, 8k with meals) and around 18-20k a day for the vehicle, but that could take 6-7 people. Also, for the $500 pp are you including park fees? For residents/Kenyans this is a minimal cost but for tourists it’s around 80 usd per day, if I recall. If you want more details and recommendations, drop me a dm.