just so you know, you can find used Hondas on Craig's List. i found a 2000 with only 25hrs. on it for $600.

also, it costs money to make a quiet generator. that said there are some other ones out there cheaper than Honda/Yamaha. they are all considered inverter generators.

Boliy, Magna, Kipor. Lifan are Chinese-made inverter generators that are close in db ratings. they are cheaper than H/Y. they can be found on Ebay, RV dealers, internet dealers. Lifan was being sold on Home Depot's website but they sold out.
Champion just came out with a 2000w inverter one that you can parallel. they can be found at Sam's Club in the U.S. and at Costco in Canada. i've heard they are selling around $499US.