Hopefully it goes well Sending you and Haley both good wishes!
This article may or may not be of use to you, Akari. It does offer some suggestions for lower cost heartworm treatment. X-rays will tell you more about what stage Haley may be dealing with.
I have had two vets read the article. They agreed with the information presented. Both vets presented the concern that owners are more likely to forget to give heartworm meds if they aren't scheduled monthly.
I am very wary of over medicating/immunizing and give heartworm meds every three months from May to November. As mentioned in the article there are less expensive options.
An even more inexpensive option is here:
Sending healing energy to dear Haley.
The Science diet for dogs is a joke, the Science diet for cats is not however.
Did you guys know that vets get a portion of the money from selling Science diet. That's why it gets recommended for dogs
Vets and Doctors get paid to recommend the meds they do. The same way big corporates used to bribe senators to gain support for their companies. It is true for almost all things your vet will use(down to the brand of needles) doesn't mean it is bad for your animal, but science diet for dogs is too high in protein from what I hear and is too big of a dietary change for most dogs to take lightly. With cats it can take 6 weeks to ween them onto SD, of course, cats have a higher protein need. SD focuses too much on proteins. Still, it is better then a lot of the big store brands. IAMs is a good brand imo, as is blue buffalo.