Elephant is a 21 day safari.
Cape Buffalo - depending on concession is either a 7 or 10 day safari for 2 cape buffalo. And i think you have limited plains game for the 10 day safari package. I think the 7 day safari was cape buffalo only for the few safari package i saw.
a 14 day safari will get you 2 cape buffalo and some plains game and crocodile.
You need a 21 day for elephant, hippo, lion, leopard and some plains game.
Prices have gone up and for a 14 day safari price including your wife, this package will be in the neighborhood of $80K.
Each package 10 - 14 - 16 - 21 - 28 day safari will usually require a trophy fee deposit. The air charter will run you between $6K and $12K depending on what part of the country you elect to hunt. The groups i have checked with did not offer the 7 day safari.
Elephants are being poached at a rate of about 30 a day and hunting for them is getting difficult. However not impossible.
A 21 day safari package will be in the neighborhood of $120 to $150K
Looking at your elephant hunting request, in Tanzania there is only trophy elephant hunting.