A word of caution.You will need both a CNC machine and an extraction system that can run for a full day without overheating.You may also need to run them for several days to get the level of detail in the sample pic.Aspire will give you a fair estimate once you have entered the toolpath details.the advice about tooling in the previous post is a very good starting point and by using Aspire you will have the facility to draw vectors around areas of fine detail where the very small tool can deal with the finer features.This is done by using those vectors to denote machining boundaries.You may then be able to use a larger radius tool for the areas with less variation in surface curvature.As I'm sure you will realise,a gently curved surface machined by a 12mm dia ball end cutter with a 0.7mm stepover will have a better finish than it would if done with a 1mm dia equivalent and a similar stepover.A finishing cut in two directions will dramatically reduce the amount of hand finishing and if there is any amount of had finishing in nooks and crannies,you probably won't enjoy the time consumed by it.Might I suggest you start with a more modest project than the item in the first post?Something abut 250mm square is enough to work out the process and still produce something big enough to hang on the wall-or feed the woodburner if it gets too tedious cleaning up the machining marks.