Calm, Binners, calm…
I'm currently using a tatty old hybrid for hacking duties atm. Keveevs found the frame outside Barclays Bikes in Dalston, just thrown away. Replacement brake spigot, mech hanger, and a host of tatty yet reasonable bits and pieces, and it's light, quick and not particularly attractive to scrotey thieves. It even has a rack that we found in the street. Can't beat a bike built from salvage. Proper Pikey Bikey™.
TBH, if I were going to buy owt that's going to be left locked up, then this £69.99 SS MTB from Decathlon would be my choice. Basic, bit heavy, but solid and simple.
SS FTW for a city commuter.