Read the AAHA guidelines. Parvo/Distemper are good for 5-7 years.
So, Jax had her puppy shots, her 1 year booster. At 4 years, I titered. Her levels are still so high she should never have to be vac'd for these again.
It's a shame you couldn't take a trip to upstate NY and get the titers done for $75 each dog for both diseases.
Even with a hotel room you would save a ton of money on them.