Looking for an used, inexpensive pre amp

Currently using a cheap but fairly nice sounding Dayton T120 D class amp.  Not enough inputs.  I would like to find a pre amp to use with this amp and perhaps at some point, if I can find the money, I can buy a power amplifier to replace the Dayton.

Figure my budget to be under $200 right now.  Looks like plenty of older inexpensive Solid State pre amps are available on Ebay.  

Any ideas what I should look for when buying a preamp?  I've only used Integrated amplifiers up to this point.