I am not familiar with any 4% lodging tax nor a 5% surcharge on rental cars. I would suggest starting out by asking the company/agent you are renting from. Without knowing the company you are dealing with, getting an accurate response is probably not going to happen.

Like Carol said, fees/taxes/charges can vary and the bottom line and customer service is what is important when making a comparison.

I would compare the bottom line and make a decision from there. Cheapest is not always best and to me, customer service means a lot.