There is no substitute for a good pro. But BM hitting is important to groove your game. One thing...the BM can hit directly to you, cutting down on your footwork. Set it where you do at least 30 minutes of side to side. Jmo
With racquet mounted on stringer, just do 8 1/4 racquet lengths for a standard 100.
A 103 and larger...I have a hook on the wall that I put string on....measure out both ends exactly...walk string back...cut at halfway mark.
Concrete courts at a hospital. The courts were built in the late 20's. They were in amazing good shape. The hospital maintenance workers painted the lines on with green lead paint!! When the ball hit a line...you knew it. Haha