Basic commuter bicycle

A heavy bag of groceries can bend an add on rack which connects to the seatpost. On the other hand bikes with original fittings machined into the frame for adding heavy touring bags are a little hard to find in lower price ranges. I would search Ebay for a cheap rack that fits at the top to cantilever brake mount studs and at the bottom to the axle (a.k.a. quick release or QR). There are many types of brakes on low price bikes, so make sure the bike has cantilever type breaks (otherwise the mount studs won't be there). Here in the States Diamondback has good low price bikes which will mount a heavy duty rack.

A good bike lock is a must on campus, see Sheldon Brown's tips on locks ("Lock Strategy"😉 at Harris Cyclery online, e.g. smaller U locks are better than larger expensive ones (because jimmying tools can't fit inside smaller U frames).

How about a nice old Raleigh Superbe or Sports three speed? They made millions of them and they were built to last forever. They're comfy to ride, bulletproof, not expensive, require very little maintenance, and are not very appealing to thieves.
I have a 1966 Raleigh Superbe that I use as a grocery getter. It has fenders (mudguards) and a chainguard so my clothes don't get dirty. A dynohub lighting system, a kickstand, a fat Brooks B-66 leather saddle with springs, and a nice sturdy steel rear carrier. The bike's upright riding position and low bottom bracket make for a stable ride even with a load. The three speed hub can be shifted while in motion or stopped and because the gearing is internal it's impervious to weather conditions. I can chain this bike up outside of a store and know it will still be there when I come out. Oh, did I mention that's it's fun to ride too? 🙂