I have also experienced this, tilly (lurcher) had blood in her diohreah and i had just moved areas and was very very skint to say the least after everything went pretty much tits up after being refused benefits from the government. So I rang the PDSA for help and i also lived outside "the area" grrr. Luckily it was only a virus and cost me £60 at the vet
Wold just like to add that I would go to the end of the earth to give my dog the treatment needed just as i would a child or a family member as i class her as part of my small family