<?xml version="1.0" encoding="us-ascii"?><InstanceReport xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"><Version>2.4.0.8</Version><ReportLongName>118 - Disclosure - Tenant-in-common Property Debt Refinancing</ReportLongName><DisplayLabelColumn>true</DisplayLabelColumn><ShowElementNames>false</ShowElementNames><RoundingOption /><HasEmbeddedReports>false</HasEmbeddedReports><Columns><Column FlagID="0"><Id>1</Id><IsAbstractGroupTitle>false</IsAbstractGroupTitle><LabelSeparator>

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</LabelSeparator><Level>2</Level><ElementName>ck0000926843_TenantInCommonPropertyDisclosureTextBlock</ElementName><ElementPrefix>ck0000926843_</ElementPrefix><IsBaseElement>false</IsBaseElement><BalanceType>na</BalanceType><PeriodType>duration</PeriodType><IsReportTitle>false</IsReportTitle><IsSegmentTitle>false</IsSegmentTitle><IsCalendarTitle>false</IsCalendarTitle><IsEquityPrevioslyReportedAsRow>false</IsEquityPrevioslyReportedAsRow><IsEquityAdjustmentRow>false</IsEquityAdjustmentRow><IsBeginningBalance>false</IsBeginningBalance><IsEndingBalance>false</IsEndingBalance><IsReverseSign>false</IsReverseSign><PreferredLabelRole>verboseLabel</PreferredLabelRole><FootnoteIndexer /><Cells><Cell FlagID="0" ContextID="P01_01_2013To06_30_2013" UnitID=""><Id>1</Id><IsNumeric>false</IsNumeric><IsRatio>false</IsRatio><DisplayZeroAsNone>false</DisplayZeroAsNone><NumericAmount>0</NumericAmount><RoundedNumericAmount>0</RoundedNumericAmount><NonNumbericText>              &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif "&gt;  &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &lt;u&gt;Note 12:&lt;/u&gt;&lt;u&gt;Tenant-in-common Property Debt  Refinancing&lt;/u&gt;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  &amp;#160;&lt;/div&gt;    &lt;div style="clear:both; FONT-FAMILY:Times New Roman;FONT-SIZE: 10pt;TEXT-ALIGN: justify; MARGIN: 0pt 0px; FONT: 10pt Times New Roman, Times, Serif"&gt;  NPAMLP owns an undivided interest in the San Jose, California  property through its &lt;font style=" FONT-SIZE: 10pt"&gt;23.9&lt;/font&gt;%  ownership of 2525 North First Street Holdings, a Delaware Statutory  Trust, and does not control the decisions over the property or the  other tenant-in-common (&amp;#8220;TIC&amp;#8221;) interests. As a result,  the combined condensed financial statements reflect only  NPAMLP&amp;#8217;s percentage of the TIC&amp;#8217;s real property, related  mortgage, revenues and expenses.&amp;#160; In March 2013, the  independent manager of the TIC property successfully refinanced the  third party underlying mortgage on the property. NPAMLP treated the  debt refinancing as a debt modification for accounting purposes. As  a result of the refinancing, NPAMLP received $&lt;font style=" FONT-SIZE: 10pt"&gt;810&lt;/font&gt; in proceeds, of which $&lt;font style=" FONT-SIZE: 10pt"&gt;714&lt;/font&gt; was recorded as restricted cash, and  assumed an additional $&lt;font style=" FONT-SIZE: 10pt"&gt;1,542&lt;/font&gt;  in wraparound mortgages payable. Also, $&lt;font style=" FONT-SIZE: 10pt"&gt;257&lt;/font&gt; in&amp;#160; leasing commissions and  $&lt;font style=" FONT-SIZE: 10pt"&gt;475&lt;/font&gt; in&amp;#160; loan fees were  deferred&amp;#160; on the combined condensed balance sheet as a result  of this transaction. In addition, NPAEP paid $&lt;font style=" FONT-SIZE: 10pt"&gt;354&lt;/font&gt; of the&amp;#160; loan fees related to the  tenant-in-common debt refinancing. This resulted in a reduction of  $&lt;font style=" FONT-SIZE: 10pt"&gt;354&lt;/font&gt; in deferred loan fees  and due to NPAEP in NPAMLP&amp;#8217;s combined condensed balance  sheet.&lt;/div&gt;  &lt;/div&gt;        </NonNumbericText><FootnoteIndexer /><CurrencyCode /><CurrencySymbol /><IsIndependantCurrency>false</IsIndependantCurrency><ShowCurrencySymbol>false</ShowCurrencySymbol><DisplayDateInUSFormat>false</DisplayDateInUSFormat></Cell></Cells><ElementDataType>nonnum:textBlockItemType</ElementDataType><SimpleDataType>na</SimpleDataType><ElementDefenition>No authoritative reference available.</ElementDefenition><ElementReferences>No definition available.</ElementReferences><IsTotalLabel>false</IsTotalLabel><UnitID>0</UnitID><Label>Tenant-in-common Property Debt Refinancing</Label></Row></Rows><Footnotes /><IsEquityReport>false</IsEquityReport><ReportName>Tenant-in-common Property Debt Refinancing</ReportName><MonetaryRoundingLevel>UnKnown</MonetaryRoundingLevel><SharesRoundingLevel>UnKnown</SharesRoundingLevel><PerShareRoundingLevel>UnKnown</PerShareRoundingLevel><ExchangeRateRoundingLevel>UnKnown</ExchangeRateRoundingLevel><HasCustomUnits>true</HasCustomUnits><IsEmbedReport>false</IsEmbedReport><IsMultiCurrency>false</IsMultiCurrency><ReportType>Sheet</ReportType><RoleURI>http://www.0000926843.com/role/TenantincommonPropertyDebtRefinancing</RoleURI><NumberOfCols>1</NumberOfCols><NumberOfRows>2</NumberOfRows></InstanceReport>
