I got the Wifi equipment from C.Crane(www.ccrane.com) in the US and they estimate up to 3/4 of a mile, I can't verify that but I do know a few weeks back I was in a campground with Wifi and fellow campers all around me were struggling to get a decent signal on their laptops and I was streaming video no problem !
The satellite is VuQube(www.kingcontrols.com) which has a remote for easy sat. pointing and I rigged up an alum. angle on both sides of my maxair vent and cooresponding angle on sat. dish base that hook together on roof, its not secure enough for travelling so need to get out my fold out ladder to put it up each time but it goes up in minutes.The cabling for both I ran through the area where my electrical hookup cable stores and then was able to feed the cabling up through the wall using the existing tv cable plate hole in the wall as my pull through point and then made new cutouts and installed new wall plates for both so I now have 3 plates in a row on my wall, the orginal tv hookup plate, my sat. hookup plate and the Wifi hookup plate.It was a little tight working in the confined area to pull the cables but a little patience goes along way.
I then have the wifi outlet cabled to a wifi repeater in the trailer so if I decided to sit outside with the laptop. I am connecting to the wifi repeater which in turn is connected to the antenna.
Hope I am making sense here if not let me know and will try to explain better. I could also take some more detailed pics which would help clarify.
I must admit I really do enjoy doing the mods and make the trailer our own. My worry is one day there will be nothing left to do and I will have to sit down and relax ! :)