All Files for mixing need to be WAV or AIFF format. 44.1kHz, 16 or 24 bit.
Please ensure that all files run from 00:00:00:00 (SMPTE) on whatever DAW you use.
Out of sync tracks will incur additional costs as the time involved in correcting this can be considerable.
Please use WeTransfer or a similar FTP service to send files, this ensures file integrity.
Mixes are charged on a case by case basis (complexity of mixes, revisions, single tracks/ EP/ Albums. But as a rough guide €150.00 per track will give you a ballpark figure.