You can expect to get what you pay for, and paying $300 or less won't get you much. For under $300, you could get a low-end resistance unit and a cheap BSO from Wally World; but your wife's back might not like that. You could get her a *real* recumbent trike, but you can also expect to take your $300 number and sextuple it for a used one; so that's not likely to work for you. The Schwinn 230 recumbent bike is $399. It doesn't fold, nor does it go anywhere. It's a stationary trainer.