They cost 25k each on average and so far they’ve been easy to self manage out of state.

It's set up for roommates and housekeeping is included. 

If it’s a safety issue, I’ll of course make sure the premises are as safe as they were before any required maintenance was done, but she is now suggesting that if I don’t reimburse her for those specific anchors, I am violating fair housing laws for familial status and/or tenants rights regarding not incurring costs for required repairs.

Your ONLY cost in a rental is the cash you come up with. 

In that environment buying in the hood becomes very tempting, but that little bit of cash flow comes with a huge cost in headaches, the probability of property damage (things like a charcoal grill in the living room) and long term you might just be treading water.Average net cash flow is probably around $200 per door after you have stabilized the property, so you need a few units before it amounts to something.

If it's beyond normal, do I just charge what it costs to fix it or do I have to discount the cost for "normal wear and tear"?

How much would something like this cost?

She called it a cash offer, but included a letter from her hard money or private lender (same thing, really) stating the lender is good to go with the deal, the lender has plenty of liquid cash, the buyer has his 20% down payment and cash for closing costs, and there is no financing contingency.3.

.: @Michael Tompkins get a HELOC I suppose a HELOC makes more sense than doing a cash out refinance since I would keep my current interest rate and wouldn't have to pay closing costs.

If you sold the quad there are costs involved, and then you have to find somewhere else to live.