As for the power supply, the kit is supplied with a US type 120vac to 12vdc wall mount power supply.  It may be used with a travel adapter like would be used for US equipment such as portable electronic devices, radio, stereo, etc...  You may request that the part is omitted from the kit and take $4 off the price.

When shopping for the 12vdc wall mount power supply (100mA or more) note the connector on the end of the part is not a concern as the instructions are to clip and solder the wires direct.  A dvm set to measure dc volts can be used to confirm the polarity of the two wires--when the red probe is on the plus pole and the black probe is on the minus pole, the reading is a positive value--with the probes switched, the reading is negative as indicated by a minus symbol before the digits.