Johnny;
First I would congratulate you for having some pretty grand plans to do some great hunts!
However you might be getting just a bit ahead of yourself.... Look at breaking these hunts down between day fees and trophy fees. You can book an all inclusive buffalo hunt for say $12,000 and a package deal on a PG hunt, then get a quote on various lion hunts, all in, etc.
Or if your wanting to combine hunts and species, look at the trophy fees for each such as buffalo and various PG, and even lion depending upon who and where your going. You only have to pay the day fees once... So say that buff hunt might break down into about 1/3rd day fees and 2/3rds trophy fees... If you get the buff before the week or whatever your booking is up, you have time to go hunt some PG for just trophy fees.
Or combine a lion and buff for a 10 day or 2 week safari.
Now I know it is fun to go back (Lord knows I know, I'm heading back for the 3rd time in 13 months!) But I spent 30 years building the funding.... In hind sight I should have gone 10 or 15 years sooner.
However there are some great efficiencies to doing longer hunts, if you can. Somewhere I pointed out the math on the cost of flights. I take my wife along so 2 plane tickets, plus domestic flights and travel and parking, etc. You can dilute that all out by spending more days and taking more animals on one trip... If you can get away and spend the money..... But it sounds like you are a master budgeter and obviously plan waay ahead!
Just another thought, I assume the field care and prep is the most important part of preserving a trophy. Certainly the first step. Then the dip and pack. Once that is all done and done well, I believe the skins will keep for years. So if your budget is tight, you could hold of on the taxidermy for a bit.
I am planning to dip and pack and get my lion home ASAP. Providing I get him, to which I am very confident. However I am not going on a guaranteed hunt so there is that risk.