I would suggest you get the regular UV-5R, not the -5RA. There are larger batteries that easily fit on the -5R, but only with a lot of Dremel work on the battery and radio case to fit on the -5RA.
Also, there is absolutely NO difference under the case. All of these variants, the -5RA, -5R+, etc, are all the same but for one, a model sold by Radiomart that will work 2m/220 instead of 2m/440.
Before anyone says, "Just program in the 220 mhz freq in a regular -5R,"... yes, you can, but it won't work due to the antenna AND the filtering in the radio will not allow it to work 220. Other than that one exception, all of the variants are identical.
About batteries, the regular battery is 1800 mah. It will last about 2 days with a lot of use, perhaps a little more. There are 3600 and 3800 mah high capacity batteries. The larger battery gives the radio much better balance and handling. It is difficult to hold the radio with one hand and press buttons with your thumb. This is quite easy with the larger battery, no fingers falling off the bottom of the radio. These larger batteries will run about 4-5 days with a lot of use. One thing about this radio, it is very efficient on battery.
Antenna, let me recommend the Nagoya NA-701. It is about 8" long and much better performing than the stock antenna. There may be times you don't need longer range and do want the smaller size. Keep the stock antenna for that. Some will tell you the NA-771 gives the longest range. It does, but it is 16" long. The added range is not that much compared to the NA-701, but where 8" is manageable, the 16" antenna is a pain.
You can buy the UV-5R with the 3600 mah battery only.
http://www.ebay.com/itm/221065959973 This is a reliable ebayer and I've bought at least a dozen or more UV-5Rs from him for fellow club members. Shipping 7-8 days.
http://www.ebay.com/itm/370482649911 Same seller, will pack it in the box with the UV-5R. 8" long. Genuine Nagoya, not counterfeit. Works very well.
http://www.ebay.com/itm/370487531741 Ditto. 16" long.
If you have a good DB-9 RS-232 to USB adapter, this programming cable avoids the counterfeit Prolific chip problem and works reliably.
http://threeoldcrows.com/shop/magento/ham-radio-equipment/accessories/programming-cable-with-db-9-9-pin-serial-connector-for-kenwood-baofeng-wouxun-radios-serial-db-9-to-type-k-2-pin-connector.html
If not, and you want straight to USB, this one.
http://threeoldcrows.com/shop/magento/ham-radio-equipment/accessories/programming-cable-with-ftdi-usb-to-serial-uart-controllerfor-kenwood-baofeng-wouxun-radios-usb-to-type-k-2-pin-connector.html
Read here about programming, etc.
http://www.ar15.com/forums/t_10_22/664274_Baofeng_UV_5R_information.html