Realize land surveying on a low budget?

Can I operate this as "normal"?

Hmm, no idea.. only "trial and error" helps here… if you meant the APP.. the same applies to the leveling thingamajig.

Alternatively, you can also try the analog method and use a [Schlauchwasserwaage]. The hose must of course be long enough. Then you can determine the height difference in relation to the ground level by the water level in the hose. Of course, this only works for slight slopes or if you have a ladder.

Properly low budget would be: one person stands "upstairs" with a spirit level and laser. The other "downstairs" with a tape measure. --> Laser hits the tape measure. Then you know the height difference and can calculate the rest. If the slope is longer than the length of the tape measure, you can repeat this in sections until you reach the bottom. Should be sufficient for a rough estimate.

that is a cool idea. I'll put the laser on a one meter high tripod then I can measure it exactly. Awesome. I will report how it was! I can have GPS displayed on my phone then I also have my approximate location. Great

Geoportal Bayernatlas have you already tried that?