In our area, Leptospirosis is rather rare and all of the vets I've talked to are absolutely fine with my decision not to vaccinate for it. Like Cathy mentioned, the vaccine only targets a few strains so the vaccine is essentially a shot in the dark, IMO.

Most vets give the DA2PP (distemper, adenovirus-2, parvo, parainfluenza). Corona and Lepto are optional. I skipped both after consulting with my vets and knowing the risk in my area. I also skipped Bordetella, but, again, that's after consulting with my vets and knowing my area's risk level and my dogs' susceptibilities.