Figure out what your towers would earn normally over the three year projection add your profit and then look at his proposal because crypto currency is an unknown - 20% share of promises is zero, in 3 years 90% of promises is still zero - if it is a money maker why give away the golden goose...
For your sand blasting cabinet, I picked up an older overhead projector - stripped the roller ends off of it and attached them to my cabinet and used Overhead Projector Film Rolls under the glass (made up some thin plastic sliders to hold the roll up to the glass). When the roll is cloudy, I...
I picked both the Walker and the vise up for $70. The tag is missing off the jack so I haven't figured out what model it is but it is still working. I will rebuild the jack this summer as soon as I get the correct model rebuild kit.
Do not "repeat" do not push the output nozzle on the gun firmly into the palm of your other hand/glove and while pulling the trigger. This action can drive the blasting medium into your skin very unhealthy. I have a piece of rubber tubing mounted on the back wall inside the cabinet for that job...
Too bad you didn't have a teenage son who wanted a concert ticket for his favorite band - didn't charge me for fill the trench in afterwards. :) Only a hundred and twenty feet in sandy soil.
If you are going to use it as a two car garage - two 9' garage doors will be fine. I used a 9" and 8" because I have to angle my car into the larger door. If you are going to use one side as a workshop frame it for a garage door but install a patio door for natural light. 24 X 32 is a nice size...