I recommend you get in contact with
Dollars5
They have done a lot of work for me on
Buzzdup Global and I can definetly vouch for them. They do good prices and their work is great. They also provide support after they have completed the work for the mods they have created, i.e if something isn't quite right. They usually do a part payment up front and then rest of payment on completion (although this may vary from case to case). They will also provide a demo of the Mod on their server before installing it on your site (again this may vary from case to case as required).