If it were me I would look for a used buggy, let someone else take the depreciation hit. The economy is slow right now, there are many people that have lived well beyond their means and are now dumping their toys cheep to stay afloat, it is sad but a fact of life. There are some great deals out there right now if you are a cash buyer. try craigs list, ebay and just put the word out that you are looking. You may have to look a couple of turds before a nice buggy pops up but be patient and you will find a what you are looking for.
After a quick search i found these, they are not cheep by any means but, Speed costs money.... how fast do you want to go..
http://phoenix.craigslist.org/evl/rvs/2063388996.html
http://phoenix.craigslist.org/nph/rvs/2062477410.html
http://phoenix.craigslist.org/wvl/rvs/2062189383.html
This one really looks like a great beginner buggy
http://phoenix.craigslist.org/nph/rvs/2060731832.html
and a very inexpensive Joyner
http://phoenix.craigslist.org/evl/rvs/2063217490.html
I guarantee you couldn't build any of these buggy's for a fraction of what you can buy these for and personally I have never paid asking price on anything I have ever bought so i would bet there is some wiggle room on the prices.
I don't know where you are from but when looking for these types of sand toys look where theres lots of sand.
I just drove 1700 miles 2 weeks ago to pick up my Pilot out in California, and trust me it was worth the drive. I got exactly what I was looking for at well below market value and couldn't be happier with it.
I hope this helps & good luck
Nick