I've never participated in the DD for a series A but have been a party to the DD for an acquisition, and it looks daunting because it is daunting. During an acquisition, not only are you collecting this information (which, if you didn't spend a constant, tedious amount of energy over the life of your company to keep up with, is itself a monumental pain in the ass, for each each step might incur several weeks of lag), but legal then bills you to review each of them. It can cost hundreds of thousands of dollars.
If you're lucky and the deal goes through you get to pay that out of the investment, if you're unlucky and the deal does not go through due to major surprises during the DD then you may end up not being able to raise at all and you'll still bear the costs, if the surprises are due to the company failing to properly disclose stuff early on that they could have reasonably been expected to know about then there is a fair chance they will end up being saddled with the costs of the counterparty.
