Can you share the model number of ac you are buying because specs are available on net and the current consumption is clearly written .. i don't think any 1 ton window ac takes 5 amp .. rotary technology may be efficient but not that much
my experience says window or split 1 ton consumes 6.5 amp (approx) ...
if u shut off gas the split ac gas is preserved in transportation and it can work on original gas no matter how many times you re-install it
the rate of ac installation in islamabad is around 1000 and unistallation about 500
the advantages of split
-- less noise
-- better cooling since both units are not attached (do not compare pakistani split with branded window ac)
-- lesser damage to walls
for 10 x 12 room 1 ton should perform good ... i have similar room size and 1 ton orient ( i don't like it much though due to poor air throw) and it consumes around 1 unit of electricity per hour