Its looks to be in great shape both cosmetically and mechanically. That's a huge plus if you don't want to/cant fix it up yourself.
Its a seriously high price for the quality of bike though. The original downtube shifters have been replaced with stem shifters. That isn't necessarily bad, friction shifting from either spot works fine, its just odd to see that replaced since stem shifters typically mean lower quality overall bike.
Try it out- at least your bro will know if the sizing is good or not so you can further refine the search.
For what its worth- many on this site seem to do their own wrenching, so a bike like this is tough to justify for pricing since they don't mind getting it into riding condition.
You could look at the bike's price like this- $130 for the bike and $170 for new saddle, components, and shop work if you were to take it to a bike shop to get into riding condition. I wouldn't consider that bike for $300 as I would hope there would be other options in that size around your area for less, but I would want the condition to be equal. No point in buying a bike for less if its in bad shape and you aren't the one fixing it up.