I should add that we have about $25k in personal debt to family for a car and another $5k on an interest free (18 months) credit card to pay for my wife's schooling.

Maybe consider peer to peer loans or credit card 0% checks

Does anyone know of any credit cards that would allow you to purchase a property with it?

We are in Canada (Maritimes) and 90% of our tenant pay their rent electronically (e-Transfer, PAD), we still have a few who pay by cheque and a couple who pay cash (translate: go to the bank or ATM with a deposit only bank card).  

How should I play my cards ?

Right now, I have about $6800 in credit card debt, another $6000 on a Home Depot card, and a $21,000 personal.

They have paid around $70k into a $170k mortgage over 20 years so far and have been constantly falling into credit card debit, renewing their mortage over and over.. its never ending.

I would make sure to take business cards, even if you have to order some from vistaprint that just says real estate investor.

I've never done that but I'd assume if you have separate charge cards per project, you can simply see statements from them....If you find something else that works great please let me know on this.

Welcome, I will recommend to go to local meetups and make sure you go with a lot of business cards.