How much will it cost to add a window?

I just moved into a new house and my room is upstairs (it used to be an attic so its complete with the slanted ceilings but maybe 2 feet of flatness at very top). It has no windows and I love the feel of a window in my bedroom. I love waking up in the morning and hearing the birds and letting the sun warm my face, but my room is exempt from windows. On the exterior of my walls is the roof so the brick wouldnt't interfere, but on the sides of the house (where it is vertical) there is just vinyl siding so there could be a window on the wall (instead of on the obtuse roof of the house which is my room's vertical walls). Can anyone estimate the cost of a standard-size metal-frame vertical sliding-glass window or a standard-size window that swings open (like french doors would)? Couild you also estimate what the average labor cost would be seperate from the window because I have family that could possibly install it at no cost. Thank you all in advance

I got windows put in for about $200-$300 each

If your walls slant down, and on the outside of your walls is the roof... you can't have a typical window. It has to be a "sky light" type window... they make them which can open still and allow air in, but they tend to be pricey. I'll get some information when I go into work.

The other option, if you're incredibly ambitious, is to build dormers... but that requires a great deal of carpentry skill and the like...

Yeah I was thinking about the dormers. (my brother-in-law calls them "doghouses" ) Thanks, id love more info on the skylights bc as I've been thinking about it, id actually like one better than a typical window, id like it to open though Spring is also approaching so it would be a good time to do it before it gets terribly hot. Thanks for the advice, very helpful!