Hi TxGirl!
Bid increments are established by Ebay. If you go to ebay and click on help, enter "bid increments" in the search field, you'll eventually get to the following info:
Current Price..............Bid Increment
$ 0.01 - $ 0.99........ $ 0.05
$ 1.00 - $ 4.99........ $ 0.25
$ 5.00 - $ 24.99........ $ 0.50
$ 25.00 - $ 99.99........ $ 1.00
$ 100.00 - $ 249.99........ $ 2.50
$ 250.00 - $ 499.99........ $ 5.00
$ 500.00 - $ 999.99........ $ 10.00
$1000.00 - $2499.99........ $ 25.00
$2500.00 - $4999.99........ $ 50.00
$5000.00 and up............ $100.00
Also, on any specific Ebay auction, when you click on "Bid" to make a manual bid, the ebay screen will indicate what the the current bid increment and what the next lowest acceptable bid is.
Jabbergah