I think you might say, "If I loaned you this, can you afford to replace it with new if you damage or break it?" If they say "No", then you can say, "Well neither can I. I have already purchased it once. Can't afford to do it again".
If they say "Yes, then you could say, "Since you can afford it, it would be best for you to go buy one for your own use. That way, mine is here for me to use when I need it."