Mezzanine Debt typically has a maturity date and involves contractual interest payments, which may be a mix of current and deferred payments.

That doesn't mean it isn't a good strategy - if the property still produces healthy cash flow after expenses (which includes future capital needs if you've deferred such), at a minimum you could be rolling the cash flow either back into the home to own it outright or using those funds to prepare for your next purchase. 

(Please note: if you are changing windows, siding, porch posts, porch structure, and any other major exterior changes ...get ready to paid more money $100.00 and meet the UDC -Urban Design Commission in which they meet twice a month to review your exterior changes for an approval, non-approval or defer which means more waiting before you get to the finish line which is your building permit for your rehab6.

There is money going into the city but a lot of the properties in that area can have a good amount of deferred maintenance.

Zillow’s Market Reports: These show market appreciation trends across different cities, helping you spot high-growth areas.5. 1031 Exchange:If you sell your current property and reinvest in a higher cash-flowing property, you may want to consider a 1031 exchange to defer capital gains taxes.

She sold it to us at a significant discount due to years of deferred maintenance—broken doors, heaps of junk, and more.

Deferred interest to end of loan / payments for a higher rate.3.

Consider selling in +10 years when there's deferred maintenance you can pass on to someone else, per @Jay Hinrichs insights. 

Under 1031, however, you must use your tax-deferred gains from the sale of the rental to purchase another investment property (or more if you'll be making a killing).

You can use a 1031 exchange to reinvest in a new property to defer those taxes.