Newbie .... want to fly like an eagle
My wife got me an Eagle II kit that a friend of ours had built for his brother-in-law who lost interest in the whole thing!
When I received the plane it was 80% complete. I did what I felt comfortable doing and then enlisted one of the club members to put in the servos and set up the controls with my "assistance".
The Eagle II is a little smaller than an LT-40, but they fly very similar. I got an OS LA .46 with my plane that I'm not thrilled with. It pulls my trainer around the air fine, but sounds like a 20 year old chainsaw with a loose muffler clamp. This noise, I've been led to believe is due to the fact that this entry-level engine has bushings to support the crankshaft rather than ball bearings. As a result of it's design, this type of engine can't turn as fast, or generate as much power as a BB engine - but they are one third cheaper!
At our field guys run all kinds of engines, the the sweetest running 46 that I've seen is the OS FX 46. This is a higher end engine made by the same company as the engine I have now. My buddy who has one on his LT thinks it is an improvement over the Thunder Tiger Pro 46 that he was running. Besides making more power, they are so smoooooth, when a plane with one of these goes by on a slow pass, all you can here is the prop going thup thup thup through the air. My LA goes rattle rattle rattle.
In Canadian pesos, the OS LA 46 is about $100.00, the Thunder Tiger is about $135, and the OS FX is about $160.00. I've actually ordered an FX 46, I'm going to put it on my Eagle, until I get my winter project completed, then put the LA back on for my wife and kids to learn with.
I wouldn't plan on gutting the trainer when you move on to something else...who knows what you will want to move onto and if the equipment will be appropriate, plus your boys are old enough to start learning now too, so they are going to need something to fly with their instructor while you are out burning holes in the sky in your 2nd airplane. My boy is 8, flying the simulator now, will be on the sticks in the spring - plus, the last two times we were at the field (bring a BBQ, make it a family affair) my wife asked the instructor if he would mind showing her how to fly. Once he came to his senses, they went off and burned up a couple of tanks of fuel and had a great time. Your wife may get interested the same way, so you'll need that plane.
Go ahead and get a new LT-40 ARF. They are not too challenging to build (one of my club mates can to a quality job of putting one together in 2 evenings) and fly great. The kit is very complete so you won't find yourself having to abandon the thing in the middle of a night of building because you need some obscure widget. Used ones are rare, and in my experience, if you can find one, you really don't want it. You should be able to pick a new one up for $200.00 or so.
Once you get to the field have a look at what everyone has for a field box, and what they keep in it. You will need fuel ($25.00), a starter ($49.00) a glow driver ($20.00), the box itself ($45.00 or so for a pre-fab, or check out Canadian Tire for options, there are pictures here on RCU for adaptations), a fuel pump ($10 to $25.00) some fuel line, and you should be good to go. Whatever you forget, you will be able to borrow at the field until you get your inventory set up. Get a small toolbox to keep all the goodies together so that whe you go to the field, you just grab your plane, your field box, tool box and go.
When you do buy a radio, if you get a new one, it should come with 4 servos, a receiver (goes in the plane), and batteries for both the radio and the receiver and finally a charger.
Well end of rant, have a ball, I know I am!