I have been playing around with the oneworld booking tool for a round the world ticket in business. Starting in the US and hitting Europe, Australia and Asia. I am getting fares between $11,000 and $12,000. Is that reasonable with y'all's experiences? I have read the stickys here - haven't found guidance I cn understand unfortunately. Any suggestions on cost and anything else would be greatly appreciated. My home airport is DFW.

I'm not sure what you mean by reasonable. The base fare for a done4 is fixed based upon the country you begin in. In addition there are taxes and fuel surcharges that are based upon your particular routing, stopovers, and carriers that usually add an addtional 10 - 20% to your total. By starting in another country you can sometimes pay less (even factoring in your positioning costs).

Thank you for that information. That's actually quite helpful. I wasn't sure it was fixed based upon origin.

Base fare is fixed on country of issue / start. Buy it and start it in a "cheap" country and you can save a huge amount - as per Jerry .. (above). The best example of this recently was issuing / start in KRT for a First Class (AONEx) ticket which was IIRC <$4000 (USD). This deal is no longer (sadly).

AA is probably a better airline to issue the ticket since they are not so generous (for other airlines) with collecting fuel surcharges.

The OW booking tool saves physically being in the start country for ticketing.

Pricing tool/ expertflyer will show you the base fare for each country, unfortunately wandreme site is not showing anymore.

Then you add the airport fees, taxes, fuel fines/taxes etc.
Generally around US$1000, less if you aren't doing UK stopovers.

So for a DONE4 (or DONE5) - after last month's price increase (and alleged decrease, from some countries), which are the "cheap" countries to start from these days?

A few are listed in this post (ignore MRU):
http://www.flyertalk.com/forum/20967855-post10.html

So I would need to get to the origin, using miles for example. That's easy enough. I don't have a credit card in another country but it sounds like that isn't an absolute requirement.

Not a requirement at all. Just use the online tool or read the threads on here and use the AA rtw desk to create your itinerary and then issue your ticket through a travel agent or an airline office or GSA (as with ex-CAI or JNB).

I was able to purchase a DONE4 last year as a US citizen through a Canadian travel agency in Canadian dollars issued by American. I saved close to $5000 and flew business for the price of a coach fare issued in the US. Unfortunately, this loophole has been closed and it's not longer possible to purchase these fares in Canada. I believe you have to purchase in the country of origin - in my case it was Egypt. This can be easier said than done, but definitely can be done. I used miles for the positioning flight to get to CAI - now I'm about to finish the last segments of this ticket and will be ending in CAI and using miles to get back home in next 10 days. Should be an interesting return to Egypt compared to this time last year....