Ron: Sorry things didn't work out for you... did you work with a Realtor? I'm finding that most of the listings these days, particularly those on the MLS where they are listed by Realtors, are priced well. They've done their research based on competitive listings and how low they can afford to go. The key motivation these days is not so much to make a profit as it is to just sell the property. Of course, there's usually some room for negotiation - but you were offering 57% of the asking price. It was just too low and your second offer was still only 64% of the list price.
If you are really serious about this particular unit, I'd re-send the offer but increase it quite a bit - sorry, I know this isn't most probably what you want to hear but I'm trying to help. I really do recommend you use a Realtor, then they can advise you on a property by property basis by researching each individual property and understanding the motivation of each seller. Every seller has their own situation - some can afford to hold out, some are more motivated than others etc. etc.
Best of luck Ron,
Villa G Realty, Inc.