I'm trying to find information on building an outdoor observation area. I live on an acre and am planning on building my kids (5 & 8) an outdoor playground/playhouse...I would like to incorporate some kind of elevated observation platform that the whole family could use.

This could be anything from just a large platform on top of everything, all the way on up to something fully enclosed with retractable roof/walls.

The latter is probably something my wild imagination is getting carried away with and would likely be way out of my budget. As to what my budget is, I'm really not too sure, I guess that would depend on how cool the end result would be. Probably anywhere from a few hundred to a couple of thousand over and above the play area itself.

Does anyone have any suggestions as to where I might start?