if your looking to do this as some sort of business I say save your money, where decent scanning is concerned theres no cheap fix, what you think you saved in purchase you lose in time fecking about with scan after scan cleaning it up and getting poor results.
there all a bit of fun 3d printing and so on.
I came to this realisation a while back and ended up using two different companys to do my scanning.
when I eventually get one it will be something like the riftek rf603b this is what I consider starting point for what I need.
the lad ive used the most is in the link depending on how long it takes to do a scan it could work out cheap till you get sorted.
http://www.1-2-3d-scanning.co.uk/