At a first approximation, your hosting costs are very obvious: you get a monthly invoice from your hosting provider. If you use multiple providers, add them up. If you use a CDN, add that in too. Very simple. Whether or not your infrastructure will be seized changes nothing about the fact that they are receiving regular invoices for the services they consume.
Revenues are similarly easy to calculate: add up all the payments received by whatever ad networks, affiliate programs, partnerships, and so on they use. Some may pay weekly, some monthly, some quarterly... whatever. But it should be trivial to add these up over the course of a 3 month, 6 month, or 1 year period.
Any competent 10 year old should be able to take the revenue and expense information and calculate a net profit or loss. Barring that, anybody in the same position should at the very least be able to consider whether the statement "I regularly dip into my personal savings to pay for the site's operations" rings true for them or if they never had to do that. If the revenue and expenses were co-mingled with their personal bank accounts, it should be easy to separate out other sources of revenue and look at income vs. expense from site operations.
True, but you're assuming they were even remotely systematic about their book keeping.
Depending on how much their income did fluctuate and how irregular their expenses might have been (especially if you consider "one time" expenses like hardware with an indeterminate life expectancy) and if you then consider that they likely had their hand in the cookie jar while also throwing "their own" money back in when they needed to, it can be a huge ball of mud.
You could determine the total loss/gain by adding up the business-related expenses and income, but that assumes they were interested in doing so.
I'm sure they had at least a general idea of how well they were doing "right now" (i.e. assuming no catastrophic hardware failures or drastic changes in revenue, etc), but unless they were certain they weren't making much money (or even operating at a loss), they had no incentive to put their exact net profit/loss into clear terms.
Considering how easy it is to burn large sums of money without really being aware of where it all went, I'd give them the benefit of the doubt that they actually didn't know if they made a ton of money. But I'm fairly certain they knew the general direction they had been heading well enough not to be honest about the specifics.
Revenues are similarly easy to calculate: add up all the payments received by whatever ad networks, affiliate programs, partnerships, and so on they use. Some may pay weekly, some monthly, some quarterly... whatever. But it should be trivial to add these up over the course of a 3 month, 6 month, or 1 year period.
Any competent 10 year old should be able to take the revenue and expense information and calculate a net profit or loss. Barring that, anybody in the same position should at the very least be able to consider whether the statement "I regularly dip into my personal savings to pay for the site's operations" rings true for them or if they never had to do that. If the revenue and expenses were co-mingled with their personal bank accounts, it should be easy to separate out other sources of revenue and look at income vs. expense from site operations.