The exact example, could I set up an LLC, get a credit card in the name of the LLC, and purchase the BiggerPockets Pro Membership with that card and write it off as a business expense?

@Mathew Zorn if by revolving debt you mean you are carrying a balance on your credit card you should not be investing at all. 

I would raise that a little bit; if the numbers work with a 15% or 20% vacancy rate, then you’ll do stellar if you make 5%.

Don't be too aggressive raising rents IF you are near market.

I would put it into multifamily.  10% COC is unrealistic here in Central Oregon in my opinion or at least my abilities, but I think you could by something with under performing rents and then over the coarse of a year or two raise them so you are getting 10% on your 450k,  That would be using leverage.  

The real question, I guess for me is really how hard is it to get the prices raised over time?

Per the City, the renter is not responsible for most costs and all of the financial responsibility due to a inhabitable area, is the landlords responsibility.All of these costs have been put on credit cards and have added up to nearly $68k.

They should have credit cards on file and have very easy ways to catch them.

If you are afraid you have spread yourself out too thin after you close, consider utilizing a 0% apr credit card just to get you started and to get your units rented out. 

Tied up a lot of deferred maintenance issues and just raised rent to still below market.