"Joked"/ hours of research and thought into the sort of thing you want, followed by scouring for parts and frame with the idea you'll need to keep an eye out, by actively looking.
I'm currently at D-1 with the one in one out rule being strictly enforced but the key to survival is making sure it isn't a one in one out and only of equivalent cost rule otherwise you need to start getting creative (start lying) secret bikes are the best bikes 🤫
The correct equation is D-1
Where D is the exact number of bikes that will make your wife divorce you.