one of the criteria is looks and compactness.
If that is your priority, it's OK. But please understand that in the lower price range, you will sacrifice sound quality for "looks and compactness". It seems like a bit of a contradiction to me. You want to buy a sound system, but it is more important to look good than sound good? That means you will be happier when the system is turned off and you just look at it?
Please think carefully about what you want, and how you want to spend your money.
Like TheWarrior said, a soundbar is a single unit that goes under or over your TV. A "home theater" usually means surround sound. And surround sound
requires speakers beside and/or behind you, in addition to the speakers in front of you. Although soundbars try to imitate surround sound, they cannot do it.
A soundbar can GREATLY improve the sound of your TV, but it cannot give you "home theater" sound. I have a soundbar under our bedroom TV and it sounds great... but we only use it to watch the morning news & weather with our coffee. My mother has a soundbar under her living room TV, and it makes it MUCH easier for her to understand TV voices with her hearing aids. So I think there can be good uses for a soundbar, but "home theater" is not one of them.