A cheper version of a sjcam sj4000 seems to work just as well as an expensive GoPro as I found out on my little jolly with Lance the other week as he brought one along with him to try out. I think Lance mentioned he paid about £40 for his. As you can see from the example pic attached its good enough for gutter clearing work.
And yes wifi enable gopro type camera is a must if you want to view what you are doing from the ground in real time, take still images, vids from your smart phone etc using the app provided. It's as simple as turning on the wifi on the camera and using the app on your smart phone to connect directly to the camera. Downside to wifi enabled gopro type cameras they eat battery life so always best to carry a few spare batteries to swap over if need be.
When ordering extra batteries, charger etc best double check first with the camera supplier you have actually bought it from as they seem to differ in actual physical dimensions. So for instance an original GoPro Hero 3+ which I use and have several spare batteries and mains fast charge the batteries may not fit a cheaper type copy.