Mary Allen
How deep you have to dig into your pocket for the Chihuahua depends on various factors.
From animal welfare
A Chihuahua from an animal shelter is often available for just a few hundred euros. Instead, these are mostly adult animals or dogs with a sometimes unpleasant history (trauma, illness, etc.).
Undocumented
An undocumented Chihuahua, on the other hand, costs less than $1000. Since the dog does not have a pedigree, it does not come from a club breed. So there is a risk here in terms of hereditary diseases, temperament, and whether the Chihuahua actually meets the breed standard. A lay breeder is not subject to any controls.
With papers
Puppies from a good and reputable breeder cost over $1000. Here you get a genuine Chihuahua from a breeder who understands his craft and breeds with great care and know-how.
Caution
On the other hand, teacups and mini chihuahuas are often offered at greatly inflated prices. These are not separate breeds, just extremely small bred Chihuahuas that have been specially selected for miniature size. In most cases, however, this has serious health disadvantages and these minis have a very short life expectancy. In the breed standard, further breeding with very small dogs is even forbidden. So better keep your hands off.