OK so I have a job that requires about an 80 foot perfectly straight run, with the wall basically shaped like an "L" overall ending against the house. (If you need a pic I can upload one). Wall looks just like the L shape, long run being the vertical part of the letter. Pretty much all of the walls I have built have had some type of curve to them, because honestly I hate straight things in a landscape design and try to avoid it at all costs. Square just doesn't work for me. But that is not possible here, and it has become increasingly frustrating trying to square things up with strings, eyes, tape measure you name it. We smartly stopped after 2 blocks starting the straight run because we knew it would be virtually impossible to line it up right and it would take us forever on top of it. Bottom line is I see these laser levels go from $100 to $600, and it looks like most are for inside. I can't make heads or tails of a lot of the descriptions so far as if they will do 2 lines with a 90 angle which is what I need. A lot of them look like one horizontal line and one vertical line which is not what I need. I need 2 horizontal lines obviously. I need one that I can see outside, will go that length and preferably has the tripod with it. Don't really care about cost, but obviously don't want to spend more than I need to if a less expensive model can get the job done. This is a pretty steep slope the whole way up and I will need it high it can't be anywhere near the ground. All I need is to be able to put it on the lower left corner of the L(position wise, not height wise), and have a 90 degree angle off the point in either direction. Any recommendations would be helpful, I know nothing about these things. I went into Home Depot and their selection was limited and I wasn't about to drop $430 on something I had not researched.