I thought about having them do it as well. They were going to charge about $650 which isn't bad but they said that all the custom mods and code I'd have to take up with the developers. Some of the functionality that my cart has is very subtle and would be easy for anyone to miss who doesn't know the full history. So... I didn't want to pay $650 only to pay 3rd party dudes another $650 plus to get their mods to work and such...
Also, I just wanted to see if I could do it!
And I did. Great sense of accomplishment and saved myself a decent chunk of change.
Now I know my cart like the back of my hand... Well... almost.
Did it all locally so no fear of screwing up my live site.
Also... for those reading that are not at all experienced with xcart and the code languages involved... I have a good bit of experience so I wasn't driving completely blind.
Anyhoo... Good times.
Cheers.