I wouldn't recommend the lens I have that's for sure. Sure you can get one for much cheaper ($100-$200) than the other long range lenses (often $1000-$3500), but no, nope, I wouldn't recommend the Canon EF 75-300mm III to anyone, lest they want to spend the rest of the day editing the photos they spent 30 minutes shooting.

Instead, for a tight budget, I would recommend something like the Tamron 100-400 f/4.5-6.3 Di VC, or Sigma 100-400mm f/5-6.3 DG OS HSM Contemporary. They are both priced around $700-$800 new, and about $600 used. Both of them have pretty good reviews.

I haven't tested them, but I'd be lying if I said I couldn't take better photos with them than my current photos.