I rented from Economy this week (Mon-Fri... 4 days). The base rental price for a mid-size SUV (Hyundai Tuscan) was $15/day thru Expedia.
They gave me a new only 7k km (that's nothing for a rental) car. I liked it.
I accepted the mandatory SLI which cover me for 80% of the liability to other drivers ($20/day)
I accepted the optional Zero Deductible 100% liability coverage ($8/day)
I declined the optional CDW/LDW because my VISA card covers me ($15/day).
I declined the optional Collision Damage Protection ($11/day)
It came out to be $43/day total. $172 for 4 days.
Then comes gas and parking. Gas cost me $50 for 4 days, all within San Jose and south (no more than 30 mins away from SJ). It should have been $40 but I filled it up too much and didn't use it up. They got about $10 of gas for free.
Parking is relatively expensive. Dunn Inn and Mona Lisa have free parking in closed lot and garage, respectively. That's pretty much the only hotels that I know that provide it. When I stayed at SL, I parked in the 24 hour lot on the street overnight. ¢8,000 for 12 hours, and during the day I either parked out in front for 500/half-hour (you pay the guy in the yellow vest and he buys the ticket for ¢365, about 25% profit for him) or ¢900/hr in the lot. Some days if I didn't go out much and spend a lot of time in my room or in the bar, and then overnight in the lot, it cost me about (8k for overnight, and maybe 4500 during day... for 12500 ($25) per day. I probably spent ¢30-40k on parking over 4 days.
Total cost, about $280-300 for 4 days.
Lesson here, when you figure out your cost, take into account the gas and parking cost because it is significant part of your total cost. I didn't realize it until this trip.