Dong Phu Vieng Trek Cheaper Starting in Sepon or Muang Phin?

There's no trekking operators in Sepon or Muang Phin.

You would have to talk to locals and set it up with them. Might require a bit of Lao language...
*****

Agree with T4F - spent a lot of time in Phin and there is no tourism businesses or trekking guides. Quite a few of the villagers go into the Park to help the local Vietnamese timber yards steal prime trees, but I doubt they'd take passengers..

Hmm, I have a very basic understanding of the Lao language now (my mother is lao and I spent about 6 weeks there last summer with my grandma) I will practice more between now and when I go and hope for the best :-) I wonder if it would be better to go with one of the locals if I could set it up in sepon or muang phin or if i should just do it with someone like green discovery in savannakhet

After reading some trekking itenaries another option would be to go there by yourself - renting a little moto...

South of Phin there is a turn off at
16°28'55.27"N
106° 1'5.45"E
saw that one, it sure is a drive road.

Next turn off at:
16°23'57.21"N
106° 4'28.09"E
this leads to the Xe Banghiang river, my guess there will be boats there to cross the river and service the village on the other side.
If you continue south there is another river crossing, this one seemingly to have vehicle ramps, so there might be a small vehicle ferry - maybe just for motos, maybe even for little tractors:
16°19'42.53"N
106° 6'22.23"E

Shortly before another trail heads into the forest, junction at:
16°24'56.97"N
106° 7'44.63"E

This trail leads straight to a small village at
16°26'59.21"N
106° 7'30.67"E
Several other villages around there.

Look up the coordinates at Google Earth...

Trekkings:
http://www.ecotourismlaos.com/activities/dongphouvieng_trk.htm
http://africanpallotta.blogspot.com/2008/01/dong-phu-vieng-npa.html
(there is a tractor in one of those images, so that village must have some road access...)
+++

Another good suggestion, thank you tools. This might be a good option for us as we are looking to try to buy a motorbike when we get to savannakhet. There is not much info out there on this tho so we may end up just having to rent one here and there for small excursions. Renting one for the entire trip would be quite expensive!

How many are you? If you are two riding on a little Honda/Suzuki with all the luggage is no fun. You would be better off renting one for a few days every now and then and bringing along only the small set of clothes for that time period.

I have seen a young tourist couple on one of those little bikes on their way to Luang Prabang, He ha his backpack between his legs, came up all the way to his chest/chin, had to place arms around it to reach handle bar. She, 4 months pregnant or more, sat in the back, her backpack hanging entirely suspended from her shoulders as it was too far back to be rested on the rear seat...

If you want to go on one with two folks on it, then go to a local welder and have a luggage rack welded on at the rear. Put small but heavy stuff between drivers legs but in such way that it doesn't interfere with your driving.

You might find more on GT riders about buyibg a bike:
http://www.gt-rider.com/thailand-motorcycle-forum/index.php
Basically I think you will have buy it in the name of a Lao (maybe your grandma or some other relative there).
+++

Haha yeah there are two of us and I was definitely going to have a rack put on the back. That couple doesn't sound too bright, his steering is compromised by the backpack and she's pregnant, hmmm... whatevs, good thing the roads in laos aren't too crowded and the farm animals know when to get the hell out of the way! Thanks for the tip about putting it in my grandmother's name, i hadn't even thought of that! Although, I wonder how difficult it would be to sell it later on down the road without her there and it being in her name...we dont plan on backtracking to savannakhet...

• I wonder how difficult it would be to sell it later on down the road without her there and it being in her name.

Dunno about that. Maybe get a sales contract done before you leave, pre-signed by the owner, just leave price and name of buyer blank?

How long are you planning to stay in Laos for that trip? Renting might be more economical...
+++

Just a thought on the rack - as another option to getting one welded up, you can buy stainless steel luggage racks that bolt on to where the handrail round the seat goes. I had one fitted for $30 on my 110cc and they are very useful - can carry anything from a rucksack to 3 cases of beerlao. Motorbike repair/spare parts shops round Vientiane either have them or can get them - they are from Vietnam.