Only a few short years ago, if you wanted to build a multicopter it invariably meant getting your soldering iron out and doing it yourself and then spending an age sitting at a computer looking at code and trying to tweak it so that your beloved copter didn't suddenly become a flying lawnmower that takes out everything in it's path. Fast forward to today and you can buy Ready To Fly copters and there is a bewildering array of frames, controllers and motors to choose from, making it a bit of a minefield for anyone new to navigate.
Safety, Safety, Safety!!!
A quick note about safety. Multicopters are not toys and have the potential to cause serious harm. Make sure that you remove the propellers whenever you are working on the copter or changing settings with power on. Before you go for your first test, make sure that with the propellers removed, the motors appear to be operating in the correct sense. With the motors spinning, tilt the copter to one side and make sure that the down going motor speeds up and the up going motor slows down. Do this for every motor to make sure that it is setup correctly. Remember to do this with the propellers removed.
For this copter it's all about keeping the costs down, but still having a capable machine that will fly well, so about $200 should easily get you in the air
As you'll probably end up crashing lots, you want a frame that can take some abuse and is easy to repair. For that reason I'm recommending the Q450 frame from Hobbyking. You can buy replacement parts from everywhere and it's only $11, so not a big investment and it's easy to mount all of your components on it. I recommend starting with a simple quadcopter and you can always upgrade to a hexacopter or octocopter later.
Hobbyking Q450 Frame
Normally for a beginner copter I would recommend a very simple gyro only board, but in this case I'm going to suggest the KK2.0 from Hobbyking. This board has been designed to be beginner friendly, has the added bonus of accelerometers which allows autolevel and has multiple firmware pre-installed for just about any configuration of multicopter you can think of.
KK2.0 Control Board
I just found this great video on how to tune the KK2.0 Board: Link to youtube
For this build we just need some basic motors around 1000kv that are capable of swinging a 10" prop. There are loads of deals on packs of 4 motors on ebay. I like these ones because they're cheap and come with prop adapters.
4x Pack 1000kv motors
Some other motors that I must mention are the X2212-980KV motors from SunnySky. These are really great quality motors and perfect for multicopters and I particularly like the propeller mount that comes with this one as it's great for multicopters.
SimonK is the name we're looking for. That's the name of a man who developed some special firmware for ESCs specifically for multicopters, which gives them a faster response time and thus smoother control for your copter. You can buy standard ESCs and then cut them open and flash the firmware yourself or buy some that have already had it done, like these ones fom RCTimer. 20A is more than enough for this build, but buy the 30A or 40A if you think that you might want to upgrade Motors in the future.
SimonK Pre-flashed ESCs
For this build the maximum size prop that we want to use is 10" and there are loads of them on the market to choose from. These ones from Hobbyking are perfect for this build, but don't forget to balance them before using them. Don't forget to purchase a right hand and left hand rotation set and consider buying different colours for the front and back of your copter to help with orientation. To do this you would actually have to purchase 4 packs of props (left and right rotation in 2 colours), but you can never have too many props and you'll be glad for the spares when you have your first crash.
9*4.7 Slow Fly Prop
10*4.5 Slow Fly Prop for SunnySky
I've covered the main components in the build, but obviously you'll need a few extra bits to complete the build, such as battery, transmiter/receiver, heatshrink tubing, power distribution board, soldering iron, solder etc... Here's some links to some extras to help finish the build:
3s 2200mAh Lipo - Cheap, quality Lipo
Power distribution board - Inexpensive but effective or buy the integrated PCB Frame
Transmitter/Receiver - Lots of functions to play with
Heatshrink Tube - Buy lots of this in lots of different sizes and colours
Soldering Iron - Must have tool for every modeller
Obviously there is a myriad of other options out there and I couldn't even begin to list them all, but hopefully this will take some of the guesswork out of building your first quadcopter. Here's some links to alternative beginner setups that come complete with just about everything you need to get started, including a couple of RTF micro-copters.
RCTimer ARTF Quadcopter
Walkera Ladybird RTF
HobbyKng micro quad
Ebay kit - even includes Lipo and charger
Please leave a comment if you think I've missed something or want to recommend alternative items and I'll try and keep this page updated.