I have built a lot of Warmoth guitars (and a few other parts guitars too). There are 2 main problems you will have. The first is easier ti fix though, that is spraying it. It is better to buy a finished body unless you are really good a spraying (and also patient :P). The second is tools. You will need some tools to put the guitar together and to set it up. I have a reasonably full set of tools, but if you only have a screwdriver, then you will need more. You might be able to get by with a set of needle files, soldering iron, philips screwdrivers and sandpaper, but that would be a minimum and you will have to be carefull using soem of them as they are not the right tools.
If you order the body and neck together and have them routed for the bridge, pickups, machines (tuners) and nut that you will use, then it will help a lot.