How we could get some places in Hongkong by MTR/bus/taxi and how about the cost ?

We will come to Hongkong from Guangzhou by bus to a hotel around Shanghai Street.Where can we buy Octopus card near there ? We are in group of 4 adults and have 2 nights in Hongkong.
Please check and advise our itinerary schedule such as :
1.From the hotel in Shanghai Street to Victoria Peak.But we want to ride Peak Tram for uphill .
2.From The Peak down by bus .We want to go to a place in Hongking GDN, Tsing Sin Street, Tuen Mun N.T.
3.From Hongking Gdn. back to the hotel.

The next day :
1.From the hotel to Aberdeen fishing village.
2.From Aberdeen fishing village to Stanley Market
3.From Stanley Market to Jumbo Kingdom Restaurant for lunch
4.From Jumbo Rest to Golden Bauhinia Square
5.From Golden Bauhinia Square to Avenue of Stars
6.From Avenue of Stars back to the hotel.
7.If we have time to visit Repulse bay, how we arrange in practical and efficient way from one place mentioned above to another place ( is it worth ? )
Thank you very much for your advice.