A basic "balance sheet" might allocate fuel needed for exploration, well development, production, crude oil transportation, refining, further product transportation and delivery to a customer. (This would vary, of course, depending on source and market.) It would seem quite important to know if we are approaching the point where producing more oil actually reduces the supply. Comparison with biofuel costs might also be interesting, but that's another question.
A recent paper seems to provide an answer: https://www.researchgate.net/publication/354885905_Peak_oil_and_the_low-carbon_energy_transition_A_net-energy_perspective There is an interesting graph, displaying the energy cost of producing more energy- in petroleum terms- over time, with an extrapolation to the near future. Thus, according to the paper, producing 100 barrels of petroleum-sourced energy today requires 15 barrels. In 2050, it will require 100, thus making petroleum based energy exploration and production economically moot.
Some numbers that may help; A consultant on a business channel ( Fast Money) said that today The cost to produce oil in the US is 55 (West TX , US dollars) , internationally it is 50 (Brent, North Sea, US dollars). These are break even costs and include capital costs , so a socialist might argue that the cost is a few percent less. That is barrel prices (42 US gallons). I do not follow oil prices but I think it is now around 62 (WT, US dollars), so the $55 cost would be about 0.89 Bbls per Bbl if converted to oil.