And just FYI, I "am" a partner in a small business. Admittedly, I don't "do the books", but I observe the gal who "does" do them, and handling all the things you describe doesn't seem to take a huge amount of her time--she spends FAR more time and agony on income tax than on sales tax.
Now, I have to ask one question----is your accounting system computerized???
Yes it is.
Here are a couple of problems I see with a National Sales tax (just as it relates to my business, I obviously can't speak for others).
1) if there are no exemptions, then what happens to wholesalers or manufacturers ? Are they going to have to pay sales tax on vendor to vendor sales or on raw materiel purchases ? Won't this drive the price of goods way up overnight ?
2) I am in a business where everybody who can, tries to pay in cash (to avoid sales taxes and to get a better deal. Adding yet another sales tax is going to encourage more people to try to use cash to avoid paying tax. (please don't tell me that people are going to change their ways just because we hope they do) Any contractor knows that folks who can, love to pay cash if they get a break on the price and just about everybody will take cash over a check, any time if only because "a bird in the hand is worth two in the bush".
If the National Sales tax is as easy as you all say it is (which I still have my doubts) then that would be great but I also believe that non-compliance would be incredible since sales tax is one of the easiest taxes to avoid paying for people who choose not to (in certain fields).
3) is every person who has a garage sale, or sells a car or boat, etc. or who gets a table at the local flea market, going to have to collect national sales tax ? I just don't see that happening.