1) If you were to go with UberX (their "highest-end" offering here) you'd typically get a Toyota Prius, which is fairly comfortable. The other car types you might get are Toyota Axio(s), which are also fairly OK, and Toyota Aqua(s) - which might be a problem, given their relatively small capacity for luggage. Kangaroo Cabs only uses Priuses.

2) Yes - Kangaroo is a great option for this - and what I typically use myself. The charge should probably be around 20 USD. I believe that they accept payment by credit card, but you need to inform them of this in advance so that the driver can be provided with a CC machine. They also allow for "pre-payment" via credit card - to do so, you'll need to call them up directly. Alternately, most drivers should be willing to stop over by an ATM so that you can withdraw cash.