Best used preamp for $1500?

The Dodd and the Modwright are very good. If you have balanced in and out, the BAT VK3i is also v. good. Now that First Sound has introduced their Presence Dlx M3, the price of the Mk2 may be getting close to your ballpark, as would a Joule. I have not had a solid state pre in quite a while, so can't comment.

For $2000 you can get a Wyred 4 Sound STP SE

You can probably get the Wyred STP-SE used for around $1500 or so. Easily everything you want in a preamp, except if you want tubes.

The Wyred STP-SE is very good. The steal of the century is probably the Doge 8 tubed pre-amp that lists at about $1,300. It even comes with a very nice phono stage, although the line stage section is by far the best out there under $4,000.

The best I have heard under $10,000 is the Coincident Technologies Line Stage that lists at $5,000. I have never seen one on the used market, but if you do you should gobble it up. It is pristeen sounding and an amazing steal even at its list price. The only down side is the absence of a phono stage, but Coincident has one, but it is more expensive than the line stage at around $5,250. But Ray Samuels has a great phono stage, the F117 The Nighthawk at $795 that is unbeatable at anywhere near its price.

You can pick up a Conrad Johnson PV-14L for just under $1500 and you will not be disappointed.