Hello all. So the fever has struck again. I'm currently looking at getting my first modern pachi and have some questions. I have found some Heiwa machines from the 90's i'm going to look at and would like to know a little about what I should look for. So here are some of my questions.

1) I know the Heiwas of this era are known to have problematic b1f boards, but how do I tell if its bad?
2) The machine is a CR so I will have to check for a card bypass dongle but where on the back would I find it? Is it easy to find?
3) What is a fair price for a late 90's Heiwa both in working or non-working condition?
4) If the machine does have a bad b1f board, has anyone here had any luck sending to board off to a pcb repair service. If I could get the machine for a steal and it would cost less than $100 to have the board repaired, I would still consider buying the machine.
5) I am currently limited to the balls that came with my two vintage machines and only have about 200, is this enough to bring to test if the machine works?
6) Anything else you fine folks also think I should know or look for? I'm a bit nervous with the Heiwas, but I rarely see modern machines close to where I live and having budget constraints prohibits buying something newer or having it shipped. Thanks Y'all