Reddit mentions: The best rotary lasers

There is no such thing as an objectively ideal fit.

Fit is about balancing goals.

For someone in your situation (two bikes with different current setups) there are three major ways to start to explore this.

1 - Make the bikes identical, and start tweaking from there as you discover "problems" you want to try and address.

2 - Leave them different and compare and contrast.

3 - Use a camera with a timer or a friend to photograph you on the two bikes and start to look at current body position vs "goal" body position and evaluate your own fit.

I'm 110% with Andrewcooke that the way to start is a bunch of cheap stems. I have everything from 50 to 130 with a variety of angles at home. Cheap stems are $10 or less used. You only really need two seatposts (straight and setback) in your fit parts bin. (TBF, that's less and less true every year as 27.2 becomes less standard)

Using trig or this great stem comparison tool you can calculate the changes to stack and reach.

Using a $50 XY laser you can easily measure your own true stack and reach numbers, and transfer fits between bikes with different geometries.

The value of #3 is that a lot of fit (and why I have paid for a fit more than once) is about you, and the rotation of your hips, how you hold your arms, and how you position your body. Depending on hip rotation you can take a "good fit" and cause yourself pain.

And last, after all that aimless musing on my part, don't rush into this, there's nothing better than miles to help you decide on reach and stack.

Saddle height, that's a different issue, that's much more black and white.

Sure thing. It all depends on the pitch of the land but if you can find a level-ish spot that works for you, you can do the following:

1. Go to supply store and get a handful (4-6,ish) of landscaping nails like this and some mason twine like this, and a string level like this
   
   
2. Spray-paint the shape where you're planning on it going. Put a nail in the ground on the highest point of the circle and tie an end of the string to it (you can either push the string to the ground or just push the nail all the way in--I'd recommend the prior).
   
   
3. Pull that string out to the other side. Hang the level on the string and pull it taught, have a friend help you to get it to read level and tie it off to a nail (or tall stake, dependent on how much of a pitch we're talking).
   
   
4. Using a tape measure or yard stick, measure the distance from the string to the ground. Theoretically, if you dig that distance down on the high side, it should level to the low side. There are more professional ways to do this but this is the cheapest hack.
   
   
5. Using the string, level, and nails, move earth until you have a level patch of dirt the size of the bed you want. Once you do that you can use stonedust and/or 3/4" stone to make a base for your pavers (or whatever).
   
   
6. All you have to do is bring the string up to a higher level and fill the stone/stonedust up to that point to ensure it's level across. That will get you the base.
   
   What's next?
   
   edits: link and word choice
   

Wow, prices have really come down since I last looked. I was looking at a few different Bosch models, and they all seemed good. Something like this

Thanks!

It's just a laser level. I picked it up when started this project. I used it for framing, tile, cutting in the niche and setting my shower doors plum. Great tool. http://amzn.com/B00NQUJ2AK

They most likely use specific Drywall Screwdrivers which have a better version of that dimpler already built into the drill. Like this one

https://www.amazon.com/Laser-PLS-60523-PLS3-Level-Yellow/dp/B00002259X

Something like that works. I've seen it in action.

I got this laser, I just picked one of the stadia rods they recommended, I think it was $50 for 16ft.

The tripod is a little shaky, but it's usually a ways off to keep out of the way anyhow, and the detector is good for an insane distance.

I figure if I use this on 5-6 projects a year, it'll last forever. The first thing I'm going to upgrade is the tripod, when I get some spare cash from another project.

This is the one I have.

It may be overkill for your application.