Hello,
I can create this web-app in PHP or PERL. But I think that PHP in more suitable for user interface. It is not a very complicated project, so using PERL would be to much. PHP will do.
I can do it easily. I did more complicated projects. Like pay per download site.
I can assure You that I will complete project by all means. You wont have post it once again. Escrow payment is not necessary. I trust You are honest, so You may pay after the work is done and everything is working. Thats my total price and it won`t change.
If You have any questions, do not hesitate to contact me. I`ll be happy to answer all Your questions.
Looking forward to hear from You,
Tristan