Obtaining a visa for Turkmenistan is not really a big deal, just costs a lot of money… here is why:
The Turkmen government requires tourist to have a guide and travel arrangement when travelling through Turkmenistan. Once you have that, you either pick up your visa at the nearest embassy or consulate or even easier, you get the visa at the border.
I inquired with two very helpful Turkmen travel agencies. You can find a list of travel agencies on the website of the State Committee of Turkmenistan for Tourism and Sport.
The travel agencies I contacted were Ayan Tours, a private office, and Ashgabatsiyakhat, a state run office. Both of them provided a great service and made very good recommendations. The one big difference was the price of their offer.
I ended up travelling with Ashgabatsiyakhat and I am looking forward to meeting their guide at the Howdan border on November 22