You could get a used Unisaw or something like that at auction. I see them go for $300 or less quite often, also in the woodworkers club classifieds....
Your floor is too flexible. Bolting it to that floor won't help. You have to get back to the concrete for bolting to work. A round blank doesn't mean...
I think it's easier turn the outside with a gouge. Using the coring tool requires several adjustments of the support arm as you go, plus you may not...
I like the idea and cannot see why it would not give you a workable result, but would still require you to finish the outside near the tenon by hand....
That would be true if the parts were fixed at 90 degrees. If the miter were bolted together and the legs allowed to move above the cabinets the angle...
A picture and description of how the door is constructed would help me think about your project. It has been a while since I worked at Condo Complex....
A miter should work fine too. I have not done a miter with wood counters. There are lots of images on the web of mitered wood counters. A counter top...