I have been writing Megillot Esther and Shir HaShirim for four years, but have not yet needed to have something computer checked (I've been careful to check everything I write during and after writing against the tikun, and I lein through every column once it is finished to double-check). I am now selling a Megillat Esther, and the customer would like it computer-checked. All well and good, but I have no idea about computer checking, as I've not needed it before. I've vaguely heard things about it - Mishmeret Stam and Tor are names I've read on this forum - but I have no idea how to access these or what the cost would be. I suppose that ultimately I have the following questions: Can I get computer checking done in the UK? If not, presumably Israel is the best option; do I need to take the Megillah there, or can I scan it here and send it to the checkers? What does computer checking cost, for the various options available? Many thanks in advance for your assistance.