Entirely personal opinion? Guide Dogs for the Blind? Well, in their last accounts they earned about £70 million, and trained up just under 700 dogs. So that's around £100,000 per guide dog.
Clue: It doesn't take £100,000 to buy and train a guide dog. It costs about £30-35k. With sat nav thingies you can put in your pocket that tell you exactly where you are, guide dogs are losing a main purpose, too.
In fairness, they do other good work for people who have visual disabilities, but the time I spent working for them was the most jaw-dropping experience ever. At the time they had a huge country HQ, staff cars aplenty, staff accommodation (because there was no need for it to be used for the people being trained up as demand was so low, they said). I'm not saying they actively waste it, just that it's become SO difficult for them to spend it. People may think they're paying for a guide dog, but now they are quite open about most of their money going into research and other assistances, plus campaigning. So people should give, but they're not really buying guide dogs very often.
Dogs for the Disabled get an income of only £2 million a year. Hearing Dogs for Deaf People get only £5 million a year. I don't think they can match the marketing campaigns of Guide Dogs for the Blind, alas, but they try.
All the accounts are available in a really easy friendly way to read through the online Charity Commission website (just put those words into a good search engine).