tbh I would side with @Marc too, try starting with around 16-??? tb, if you want to make a McChicken every week.
Though 32tb for me gives me 200 BURST a week so (200/7) / 32 = 0.89 BURST a day for each TB.
If you are into small earning then go ahead, I won't stop you, but just recommended by me and Marc
To break electricity bills, you would need 3 tb at the minimum, or to make around 3 cents per day because HDD doesn't use that much power.