Hi, most don't have a built in speaker so if it's for watching films etc you would need at least a set of speakers and at best an amp with speakers.
I have a Benq 1070 which is full HD and 3D. I project to around 110inch at ab'out 3m and its viewable In full day light.
You need to work out your throw distance and wanted screen size. Eg screen is 3m away and I want to reach a 100 inch screen then you need to find an amp capable. Some people may want a 20M throw to a screen of 150 inch. Think of it like a torch when you twist the end to get a finer dot.
This is a bargain.http://www.richersounds.com/product/projectors/optoma/h181x/opto-h181x