One handy tip for budget shoppers is to hunt for an Android with a microSD card slot so you can affordably expand internal storage. That way you can buy a handset with a small amount of built-in memory -- hopefully meaning your initial outlay is lower -- and bulk the storage out on the cheap with your own SD card.
Above all, do your research before splashing your hard-earned cash. Reading reviews is great but there's also no substitute for getting your own fingers on a phone. Take a trip to your local mobile shop to check out your options before parting with the contents of your piggy bank.
Make sure to check out how much older phones are going for, too. You might find higher-end mobiles from a couple of years ago for a bargain price on Amazon or similar. Some of these might provide more power than more recent low-end phones, but make sure to properly compare what each offers.