I don't consider that a lowball offer. It sounds like an opening offer to me to see what kind of flexibility you have.
Condos are tough to sell - it is hard to get FHA approval for many units these days. Is your condo approved for FHA financing? You can ask your agent to contact a lender they work with to get the checklist.
If FHA doesn't approve it, then it is up to the bank - and that is 5, 10, or even 20% down
If you want to sell, I would suggest you counter and try to get it under contract. I have had sellers who turned down an offer and then a year later took a much lower offer - so the risk is that if you turn down the buyer, you won't see another one for a while.
Have you had a lot of showings? Have you had any other offers? How does this offer compare to the one that fell through? If you are seeing a lot of activity, then I would say it is fairly priced. But if this is the only offer you have had and you aren't getting a lot of showings, then condo prices in your area may have fallen again.
Obviously if the market turns around, you may be able to get a higher price - BUT - no one knows when that will happen and no one even knows for sure if prices won't drop more.. all you can do is figure out what is best for you right now. If selling it is best, then do what you can to sell it!