Here's my take on it. You have to ask yourself this: do you want to produce 1 pastel ghost or an army of them? If your answer is the latter, then I think your best bet is to pick up a female hypo and a male pastel het ghost. What this will allow you to do is increase your odds to 1 in 4, but more importantly if you happen to produce a male pastel ghost, you can breed him back to his mom (the hypo) and ALL the offspring will be ghost, half of which will be pastel ghosts.
Here are some APPROXIMATE cost breakdowns and a few different approaches for you:
1. Pastel het ghost male and ghost female
Estimated Cost: Female $2000-3000 Male $6500= $8000-9500
Odds: 1/4
Advantages: NO POSS HETS!!! If produce male pastel ghost, it can be bred back to mom producing an army! Ghost adult females are worth their weight in gold.
Disadvantages: what if the female doesn't breed...all your eggs in one bucket
2. Pastel het ghost male and X het ghost females:
Estimated Cost: $6500 3-5 x $600-800= $8000-9000
Odds:1/8 x 3-5
Advantages: Multiple females decreases your risk a bit.
Disadvantages: Making poss hets (YUCK!). Might be difficult to find a reliable source to sell you enough het ghost females.
3. Ghost male and pastel het ghost female
Estimated Cost: $1500 $7500= ~$9000
Odds: 1/4
Advantages: NO POSS HETS!!! If produce pastel ghost male, you could breed him back to mom and go for the 1/4 chance of producing a superpastel ghost!
Disadvantages: Once again...all your eggs in one bucket.
4. Pastel het ghost male and poss het ghost females
Estimated Cost: $6500 8-10 x $250= $8500-9000
Odds (taking into account the odds that the snake is het ghost as well as the odds of hitting the 1:8 pastel ghost): 66%ers: 1:12.12 50%ers: 1:16
Advantages: A possibility of producing LOTS of ghosts and pastel ghosts.
Disadvantages: 1. Making poss poss hets. 2. Trying to find a reliable source to find 8-10 poss het ghost females is even more difficult than finding het females. 3. There is always the 1:1024 chance that if you buy 10 50% poss hets, NONE of them will be het.
Hope this helps.
Matt