i3 Noob cost consideration

I'm considering building an i3 single frame (the aluminum frames seem easier and stronger than the boxed plywood) and I'm wondering how easily I can build one for $400. I was looking at complete i3 kits and they are $700-800. Buying parts and incomplete kits off of ebay seems to be a lot cheaper. Here's how I've been pricing things so far:

$160 with shipping: Single Plate Frame, Rod, Bearing and Hardware Kit (frame, bearings, rods, nuts/bolts) -it seems that it includes parts (the non-printed parts) for the extruder

$50 printed plastic parts (ebay)

$25 RAMPS (cheap RAMPS from china)

$50 for 5 nema motors off of ebay

= about $300 with shipping

+ $? for heated bed and controller power supply

Could I build the i3 with $400?
I was looking on the i3's reprap wiki and I'm not really sure how to price the extruder/heated bed. How do people go about buying extruder parts/heated bed? Is there a nice parts list which explains how to go about buying parts for the cheapest decent extruder/heated bed?

It would be great if you guys could tell me if I'm on the right track or to Google around some more.
Thanks,
J50

Sorry but i think you will struggle to keep it under 400 dollars
You still need a controller PCB , a hot end , endstops, power supply etc

The 160$ kit seems pretty good value but depending on the cost of just the prusa single plate frame you could try and source the other items locally.
M8/M10 threaded rod is a standardized item and i,m sure you could get it locally very cheaply.
Its down to what you prioritize. Ease of build or cost

Good luck

Thanks for the plug. I'm the guy with the plate, rod, hardware and bearing kits. You aren't going to make a $400 build on a single plate aluminum i3. It will be closer to $500. There are i3 box kits out there that are price competitive but it's that waterjet cut plate that adds the cost.

Thanks for the replies guys. I'll be fine doing this with $500. I'm going to be busy for a couple weeks and might start building one next month. The required parts documentation is much better for the i2 than i3. When I figure out exactly what I'm doing I'll list out the parts here and ask if it all works out. Also, vegasloki, for which type of hotend/extruder are those parts in your kit for?

Thanks

The fasteners are a general assortment based on what I've been using which are Greg's/Wade's hinged extruders with J Head and Prusa Nozzle. I don't use springs on the two bolts that act as hinge tensioners. There should be enough fasteners to either a direct bolt to the frame (with M3 x 10) or a bolt through with a 1/4" plate (M3 x15 with lock nuts) In the next week or so time permitting I'm going to offer bags of fasteners in single sizes for those that want to mix and match or have a model that doesn't quite fit the BOM. Accommodating different counts of the same fasteners isn't a problem though these counts seem to be working for most people.

There is more documentation for an i2 but it's been out quite a while longer. As the i3 progresses those of us that build them will offer and modify the docs so that in the not too distant future there will be as much i3 documentation as there is i2 documentation. The calibration is the same but the frame construction is quicker and easier, requiring fewer parts.

why not go for the laser cut frames like twelve pro get your rods locally i found well cheaper than ebay i know im in uk but would imagine same anywhere else. Now you can get cheaper motors i got mine through aliexpress and from wantai took a month but $57 for 4 nema 17 48mm and i got ramps from gadget3d at $87, but i do agree around $500 for i3 alu plate version