I process my negatives myself. I set up a darkroom about two years ago. There are three or four service labs here in Rio that I could use, but that would make everything much more expensive. I would suggest you do the same. You wouldn't need to set up a darkroom, you see. Instead, you could use a changing bag like this. I also import films and chemicals, which is also less expensive than buying it all here (for some reason, films and chemicals are delivered to me so that import taxes are not charged. But This does not apply to cameras, lenses, flash units, etc.). Freestyle has good film sold at very good prices. Check the Arista brands.
As to enlarging, I also do that at home. If you dont't want or can't set up a darkroom, how about having your film scanned? Then you could have only the negatives that matter enlarged. That would lower your costs too.