Yes. Most of those are just costs. I'd replace that with building a customer base and doing the math for how much of it you need to keep income over costs. That's what kills most business ideas.
I tried my hand at being an independent consultant for a while. I hated having to manage everything myself. Realized I want someone else to handle all of that and just want to show up, do a job, go home. Much happier working for others. Might be a personality thing.
Mine is great, I wouldnt trade having a narrow set of well defined goals and a known set of giant pains in the ass for the plethora of ever changing issues a small business startup has to deal with.
Rather brave to believe that you'll have a product, an engineering departement, a marketing departement, a support departement or any employees in your startup.
I once wrote and sold some extremely shitty software, most of the effort was in the testing and support "departments", which were merged as I just had my (fortunately mostly very patient) customers work through the bugs with me.
The best case scenario while living a capitalist way of life is to be the exploiter. Sure some can save up to buy their emancipation from the economic system, but they will always be behind those who take advantage of others.