user774: At this stage, my finalized design includes Arduino Nano 3.0, a breakout board and a few electrical components on a breadboard. 
Will there be an appreciable cost savings from not buying a ready-made Arduino? The Arduino Nano clone being used costs $17.20. 
And is it a good idea if everything is soldered on to a custom fabricated PCB board, including the components of Arduino Nano 3.0? The PCB board will cost around $10 at the quantities I'm starting with.

user497: You can probably do a lot better than $17 but not much better than $8:
http://www.ebay.com/itm/Mini-USB-Nano-V3-0-ATmega328P-5V-Micro-controller-Board-For-Arduino-compatible-/130977189883?pt=LH_DefaultDomain_0&hash=item1e7ed94ffb
If you don't need USB, you can use a Pro Mini and they go for about $4 and that's really hard to beat.

774: <p>At this stage, my finalized design includes Arduino Nano 3.0, a breakout board and a few electrical components on a breadboard. </p>

<p>Will there be an appreciable cost savings from not buying a ready-made Arduino? The Arduino Nano clone being used costs $17.20. </p>

<p>And is it a good idea if everything is soldered on to a custom fabricated PCB board, including the components of Arduino Nano 3.0? The PCB board will cost around $10 at the quantities I'm starting with.</p>
 497: <p>You can probably do a lot better than $17 but not much better than $8:</p>

<p><a href="http://www.ebay.com/itm/Mini-USB-Nano-V3-0-ATmega328P-5V-Micro-controller-Board-For-Arduino-compatible-/130977189883?pt=LH_DefaultDomain_0&amp;hash=item1e7ed94ffb" rel="nofollow">http://www.ebay.com/itm/Mini-USB-Nano-V3-0-ATmega328P-5V-Micro-controller-Board-For-Arduino-compatible-/130977189883?pt=LH_DefaultDomain_0&amp;hash=item1e7ed94ffb</a></p>

<p>If you don't need USB, you can use a Pro Mini and they go for about $4 and that's really hard to beat.</p>
