It's a nice bike. But needs the usual critical eye to determine any issues.
Check frame and fork for issues
Check Headset and BB
use a chain checker for the chain - chains are cheap (relative), but worn drivetrains are a pricey fix. If the chain is over 1% stretch, then there's a chance the cassette will have cogs which 'jump' (too worn) when a new chain is put on. Check the chainrings for wear on the teeth.
check the brifters for function - expect to replace all cables.
Shimano R500 is one of their lower wheelsets, but very serviceable, and long lasting, run smoothly/nicely. Don't expect to fit anything greater than 28mm tires on these. But a good wheelset. I have about 10K on a set I have - I was about 150 lbs, for most of that riding... Not sure how they'd work for a Larger rider (190 lb +)., but prolly ok.
Conti ULtrasport tire is mid grade for Conti, but still a good quality tire.
That seatpost is a Thomson or thomson type variant, where offset is done with a kink in the post. Seatposts are an easy replacement... But this is prolly serviceable.
Given that, at a 56cm size, it'll prolly be a rider with minimum 33 ish inch cycling inseam...
Should always go into a Used Bike Buy expecting to replace some stuff...
But if frame okay, and most of the stuff is ok, then there's a ton of riding to be done on that bike.
Listing is at $700... you say $450... It's worth what you think it's worth... Given the current bike market, you'll have a hard time finding anything close to that price. Think more like $1.5k to $2K new
Big IF is sizing... which depends on you.
Ride On
Yuri