Wifi Repeater Setup And Operation?

I have a wireless access point/modem at one end of my property (which I cannot relocate). To improve wireless connectivity on the other end of the property I am thinking of placing a wifi repeater (probably a cheap one like http:[URL]... mid-point in the property. However I don't quite understand how these things work. I assume repeaters, extenders, boosters are all the same thing?

Does the repeater actually create a new seperate wifi network, so I will effectively have two wifi networks/SSIDs? or will my wireless devices still see only one wifi network? If it creates two wifi networks what happens when I move through the property with say a laptop, will the laptop need to disconnect from one and reconnect to the other hence interrupting the connection? (which is not ideal).

Also does the repeater take up an IP from my main wireless access point/modem? My setup uses a block of static IPs and hence I would prefer not to waste an IP on the repeater if possible.Homeplugs is something else I'm looking into but that seems to be a more expensive option. With Homeplugs I would disable the wireless on the main access point/modem. Then use the Homeplug to put a wireless access point in the centre of my property hence giving fuller coverage.I've also tried higher DBi antennas (& directional ones) but they have not been effective.