i'm planning to get a dog of my own...

If you are plaaning to get a Dog then you should go for a Doberman or a German shepherd as they can fullfill both of your needs.But do buy a baby dog....

A good guard and house dog that is low in price and maintennace is a japanese spitz. If you're looking for a large breed, you can go for labradors or golden retrievers, both of which requires only minimal maintenance and regular exercise, difference is that labs do better with kids and GR's can be guard dogs (lab's can't).

I am not an expert because I'm a first timer too. But I decided to get a chow chow and I don't regret it.. I think it will depend how do you plan to take care of it. For example, chow chows needs to be groom atleast 2x a week while shih tzu lhasa apso, poodle (and other alike) needs to be groom as often as possible, do you have that much time to groom them? It also depends on how much space you have for the dog, toy dogs are toy dogs, most of them don't grow/gain that much weight as much as other working, sporting and non-sporting dogs. Guard dogs needs to be walk as often as possible, can you do that? you might wanna check out this link to : http://www.proplan.com/breed_selector/breed_selector_frames.aspx good luck! :)

the best thing for you to do is to decide how much time you have and how much room you have for the dog to play. i have a jack russell and two pit bulls. their temperments of all three is that you don't want to leave them alone for any long period of time as they all love to chew and play, where as my jack russel is small he likes to get into things such as the trash, or even small places that the two bigger ones cant get where as my two pits they have had fun litterally chewing my furniture as well as my wall at my bathroom wall. always make sure you research the attitude of your breed before jumping in. I wouldnt trade mine for anything though even with the problems with their behavior when i'm away. there great and get along well dispite what people say about pits