I'm sure Enterprise Ireland have some data available. You might be able to get something from them
Alternatively there's the IIA (
Irish Internet Association) who should be able to help with some figures.
In terms of sample plans... I suspect you might find a few knocking around online
The kind of costs to factor in would vary on the type of thing you're doing.
You may want to consider:
- hosting
- ssl certs
- merchant accounts + fees
- merchant gateway fees
- programming
- marketing
-trademarks (?)
- staff
- marketing (online + offline) - you would probably include
seo here as well I suspect ?