Quick one..

If you can do it all... seems South Africa to Ireland is easier ... and cheaper :) probably...

You can then arrange bike to be shipped from there ... maybe fly back with if for a holiday and sell it.

Right. So buy a bike in RSA - get the carnet there. Ride up to Cairo, get boat to europe and all the way home.

Follow that - but why would I need to ship the back back to RSA from home?

I thought all I have to do to get the carnet deposit back is send back the actual carnet document?

This blog post should answer most of your questions (bike must return to country of origin). Everything it states in the blog about a CDP for South Africa will apply to your home country - including the ability to purchase a CPD BOND - where you pay an insurance fee on a returnable deposit. Hope that helps. https://blog.tracks4africa.co.za/2888-2/

Just check the position in Ireland.

When you take your bike out of Egypt you have to take it into somewhere else.

For me in the UK i would have been ok to pass through Europe (i think) but once in the UK I would have had to pay import duty and Vat. I sent my bike back to RSA to avoid this obligation.