Leachies can be very expensive. I've had 8 over the course of gecko keeping of various locales.
Yate and Mt. Koghis I believe are the largest and you're not likely to find one without spending a fortune (upwards of $2000. USD)
Grand Terre animals do get quite large. My two mixed GT adults were up over 230g a piece. They were a little more affordable and I sold my mixed GT pair for 2200. USD
The smaller locales are often mixed and usually in a more affordable price range. Females are way less expensive as there are way more of them. Males are gonna cost more. My Nu Ana male cost me 1200 USD.
My offshore mix female cost $500. Though she could probably go for a bit more.
As far as for a baby, you're not likely to see anything under $350 USD +shipping for a mixed offshore locales.
From my only remaining pair, I hatched 2 babies last season. I sold them both locally to good friends for $350. Next year if I have any others hatch, I will be listing them publicly for $400 +shipping.
You might be able to find a better deal at a show or with a local breeder if you can find one. But either way, they are gonna cost you a pretty penny.
The good thing about the smaller offshore locales is that they often have more pattern and better color as compared to the larger locales. So you won't spend as much and (in my opinion) you'll get a much cooler looking animal.