Perhaps the only thing more sure than death and taxes is death plus taxes. If you think the government is going to allow you to take it with you, or allow any of your heirs to get all of it, you're living in fantasy land.
It is possible, particularly if you and your heirs are very, very independently wealthy and can afford to buy lawyers, judges and congress members by the dozen to beat the tax collector out his many pounds of dead decaying flesh, but it ain't easy. Anything that you leave anyone -- except for some certain charitable organization controlled by rich people, that equals more than a pathetically low threshold is subject to the inheritance tax.
In other words, to put it bluntly. You can leave your dog or cat a roll of general purpose, brand new postage stamps and Fido or Fluffy won't have to pay taxes on the stamps or have them seized by Uncle Sam. But leave them a stamp album with a few valuable "covers" in it and they're deep in doggie doo doo and kitty litter. By the time the Feds are done with them they'll be cursing your memory for not inflicting the treasures on your ex-spouse instead of them.
Let's say, for the month, the instead of being the deceased, you're Fluffy or Fido and have just come into your inheritance -- or your "expectations" as they were called in Dickens time, when the courts which handled such matters were notorious for stalling probate cases for years and in some cases generations.
So your dearly beloved leaves you a '64 partially restored Mustang, a house that's mortgaged for more than it's worth, a couple of early generation big screen TVs and a library of 10,000 books. First thing, since the value of things like not-quite-restores classic cars and books is rather elastic, you'll have to do is dip in your pocket to hire an assessor to put a value on the estate. Then you calculate the tax due based on the annual schedule for that year and pay it sometime within the nine months after the estate has been probated.
If you're lucky that will be the end of it. If you're not the government will come after you claiming you underestimated the net value of the estate and cheating them on the amount due. You, of course, will appeal their attempt to overinflate the value of Uncle Ned's Mickey Spillane collection and, eventually, you'll reach a settlement that will satisfy neither you nor the taxman.
But it will keep you out of the slammer and that's always a better thing than the alternative.