Help deciding: used Trek Alpha 2.3, Cannondale Six13, Specialized Roubaix or Trek Domane carbon?

Have been deal hunting for a while.

I have a dirt cheap fixie for commuting but I want a speedy, fun bike for racing and adventuring.

I live in an expensive city which is reflected in prices.

[IMAGES HERE](https://imgur.com/a/byW2iLa)

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Trek Alpha 2.3 $450 – Shimano 105, seems to have aftermarket Easton wheels

Cannondale six13 $450 – Tiagra

Trek Domane $600 – Tiagra

Specialized Roubaix carbon $600 – 105 and Ultegra

by jvonm