hi, since you'll visit Macau and Guangzhou, I suggest you stay at hotels at Tsim Sha Tsui Area, for the cheapest, you can stay at City Econo Guest House.
Here is suggest itinerary:
After arriving at Hong Kong Airport, take Bus S1 to Tung CHung and then store your luggage at Citygate Outlets, after that take Ngong Ping 360 cable car or Bus 23 to Ngong Ping Village to the Giant Buddha and Polin Monastery. After that take Bus 23 down the hill and pick up your luggages (or you can put your luggage there and pick up it after your visit to Disnetland) and head to Disneyland. After the visit in Disneyland, you can take MTR to Jordan Station to City Econo Guest House.

When traveling from hotel to Macau, you can take MTR to Central Station and then take ferry at Hong Kong Macau Ferry Terminal. The ferry ticket is around HKD140-150 per each and the MTR fare is around HKD10 per each.

When traveling to Guangzhou, you can either take train at Hung Hom Train Station, thsi train station can be accessed by taking taxi, since you are a group of travelers. The train ticket costs HKD295 per person.

thank you so much that is really very informative...by the way I have another question...how much is the rate of econoguest house per room and that is good for how many person? And how can we get a visa in guangzhou? how many days its going to take? can we get it in just one day?