seriously.. most people who are afraid of over-vaccinating their dogs just do titers every year instead of vacs. The titer is a blood test to show where the dog's immunity level is at. Titers can be more costly, and you would have to pay for a separate titer for each disease.
Rabies vaccine is required by law.
You do want to be sure your dog is safe from distemper and parvo for sure.
Some diseases depend on your dog's exposure. If its around other dogs alot you will want canine hepatits and bordatella as well.
If your dog is a hunting or working dog you will want it to be protected from lyme and lepto.
Lepto vaccine only protects against the 4 more common strains, out of 30-some strains!
I am told corono is unnessecary in a healthy adult dog because only puppies and adults with compromised immune systems can get it.
Corono and Lepto are the 2 main vaccines that cause vaccine reactions, expecially in small dogs.
My advice is to read up on the diseases and to see how they are contracted, determine from there if you feel your dog is at risk of them. If your dog is low risk, it may not be worth vaccinating/titering your dog for it.
If your dog is a breeding *****, you should have her vax'd for everything so she has the immunity to pass on to her unborn puppies.
Also some people also choose to just have their dog vaccinated every 3 years instead of yearly.
If your vet is not comfortable with titers, leaving vaccines out of the plan, or doing the 3 year shots, find another vet! Vaccination protocalls are changing, and if your vet is still a firm believer in yearly vaccinations, he is not following up on changes.