Before you say you cant afford a hybrid, lets take a look at the web site, base Prius $21,100, base Corolla auto (apples to apples) $17,110, difference $2,715, City epa for Prius is 48, Corolla 26 Presuming that is the best you could do in either car (not likely) the Prius would use 250 gallons of gas a year, the Corolla 461 presuming your 12,000 per year driven....@ lets say $4.50 a gallon you would save $949 per year/ 2715=2.8 years for break even, then you would save oh I don't know $1000 a year in gas, not to mention be driving a MUCH cleaner car and doing your own little part to reduce the use of fossil fuel.
As for the batteries, Honda has had Hybrids since 96, Toyota about 98 (not positive) if there were massive battery failures, don't you think there would be a public outcry by now? why do you think no one really knows what it would cost to replace them? could it be not many are replaced? If it were a common item, I can assure you, there would be a price attached to it. By the way, Brakes last much longer in a Hybrid due to the fact that much of the forward energy is converted to electricity when stopping.
So, Lets recap, 10 years ownership, Prius, car and fuel only $32,350, Corolla, car & fuel only $37,855, so, looks like you can't afford to save $5,505?
I am not a fan of the Prius BTW, I prefer the H>