voltage stabilizer suggestion needed

Hi, myself shashi want to buy a voltage stbilizer for use at my home to step up voltage from around 130-150 V. Dealer looking the equipments/load of my home ie. 20 bulbs, 10 fan, 1 TV, 1 freeze, 1 computer, 1 washing machine, 1 geaser and 1 submersible pump of 1HP, suggested to go for 5KVA capacity stabilizer, which he is having two models one of 14 amps and other of 22 amps. he is suggesting for22amps model but telling that 14 amps will also work.
Can you suggest me for the correct capacity of stabilizer with current rating. Please describe what role will the current rating of stabilizer will play and also describe how the calculation has been done for the above said load.Also what capicity will do for the pump only.Thanks. (shashi.skp@rediffmail.com)