I live in KS and leave the boat at LOTO. Had it CG Registered when I purchased it. I had to prove that I paid sales taxes first time I registered the boat. CG Documented boats still have to have MO registration tags that are good for 3 years. Also pay MO property tax every year. The property tax formula is based on NADA and the mill levy of county of where boat is located. My 1986 Fountain costs about $450 per year in property tax. Most of it goes to schools.
After I did all of that, I wondered why I had it CG registered. Doesn't seem to have any real advantages when all is said and done.