I would appreciate it greatly if anyone with experience in commissioning PCB production and circuit manufacturing could advise me as to the following:
-A recommendation of a cheap PCB production and circuit assembly service (Emphasis on cheap, China is okay).
-A reasonable price estimate for said cheap service.
-Other relevant advice.

The board/circuit in question is essentially a small switch-mode power supply with the following criteria:
Aprox. Dimensions - 3cm x 4cm
One layer
All components smd (no holes)
Aprox. 10 components total
Of aprox. 7 or so different parts
Lead free
Initial order of 500-1000 not including prototype
Delivered to USA

Thanks for any suggestions!

 

I strongly advise you not to use a cheap production and fabrication vendor for the initial run. SMPS circuits are cranky enough without having to worry about the use of substandard components, poorly etched traces, and underweight copper. Go to a quality house, raise your price on the initial run and then work on cost reduction. You won't make much profit or stay in business long term if you go cheap and most of them are returned for credit.