First of all, what's your budget?

 

I'd say then to pay the builders 1 Ecodollar for every 4-5 blocks placed

 

i think per stack20 bucks

 

No.

 

Just hire builders and pay as little as possible.

 

well i payed 15k for flatting my 200x200 town to myminecrafter 2001.

 

When I needed one layer of a 200x200 farm filled in with dirt, I paid $1 per dirt block placed.
What I did was a had a bunch of double chests that I filled with dirt and I locked them all and then just added 1 person to each. Then once they ran out, they contacted me and I went and checked and payed them $3,456. If they wanted to do another double chest, I added them to another full one or filled theirs up again... and so on. It went pretty smooth and everyone seemed happy about the price they were being paid. :)

 

but there might be a scammer.... what if he thorw 1000 dirt somewhere and only places 2000? i dont like this method of flatting towns.

 

Sadly there is no fool proof way to not get scammed on a job such as this, unless you're standing over them watching their every move. You just have to look around and estimate what should be done when they contact you. Common sense says if not a lot is done and they went through a couple double chests... then maybe you should find someone else.

 

I pay 1k per chest and 2k for dobule chests, and people seem to place them just fine.