A lot of NatSocs are actually highly capitalist

Strong disagree.

I know. If you argue with them long enough, they'll basically admit to you that they are Socialists. I've done that here.

Some are for the most part 100% free market

Completely false. There has never been one free market National Socialist. Every single one, without exception, balks at free market positions because it means refusing to pass racial protectionism. A completely free market would even go as far as open borders. The fact that the National Socialists see the state as the extension of the nation, would make this position utterly untenable. National Socialism has always touted itself as an alternative to Free Markets and Communism, which is why it advertised itself "The Third Way" in economics, and promised the growth of a free market and the benefits of Socialist government policies and directions.

Most are white supremacists also but some are merely white nationalist and some are even okay with non-whites as long as white people maintain their dominance in their own countries.

Only temporarily. National Socialism, unlike Fascism, requires a 'purity of the blood'. Literally, the purity of the blood, and the purity of the soil, (blood and soil) interact to create the only nation capable of forming a civilization (Aryans). By their own point, only the Aryans can create civilizations, and all civilizations collapse due to the impurity and mongrelization of the blood and the soil.

In order to fulfill the objectives of National Socialism, the population must be synchronized into the Volksgemeinschaft, as a single racial body politic advancing Socialism, and the Socialist Utopia can only come from a purified body politic. This is actually the ideological core of the holocaust. Where Marx argued that jews would disappear with Capitalism (because they are one and the same) as the new Socialist Man was formed, Hitler (and other State Socialists) believed that jews had to be removed first before the population could be synchronized into the body politic that would create true Socialism. Removing all of the jews from all of Europe was going to save Europe from the collapse of Capitalism and Bolshevism, and allow Socialism to rise.

As such, no impure blood can be allowed in the National Socialist state. Racial regulations are an imperative, and eventually all mixed bloods must be removed or otherwise dissolved. The best a National Socialist could honestly argue for is mass deportation of whomever they consider to be impure.

The idea that NatSocs are commies or don't share commonality with American Founding fathers and their classical liberalism would be wrong.

National Socialists come from German Philosophy whose Collectivism and reliance on the Hegelian Dialectic stand it absolute opposition to British and English Liberal Philosophy. That's just the core philosophical basis. Economically, National Socialism stands in direct opposition to Economic Liberalism and Individualism by being Collectivist and Socialist. National Socialism is openly revolutionary against the entire Liberal order and philosophy. The idea of the Liberal concept of a Nightwatchmen State, made of a Republic, that exists to protect property rights as it's primary legal framework; stands in total opposition to the National Socialist concept of a totalitarian Ethical State, made of an Democracy, that exists to be the eternal vanguard of Socialist revolution, and the epitome of the population's efforts.

National Socialism is not only incompatible with Liberalism, they physically can't co-exist without killing each other. National Socialism is antithetical to all aspects of Liberalism, which would advocate for the violent overthrow of the state in order to Liberate it's people. And, the Liberal state is antithetical to all aspects of National Socialism which would identify it as a mongrelized, individualist, hive of Judeo-Capitalism, which would need to be eliminated to prevent the end of civilization itself.