TDSR(Total debt service ratio)=(payment of principal and interest on mortgage+property tax +heating costs+50% of condominium fees+payments on other personal loan)/grss income. TDSR guidelines Currently range 0 r N+ k; Q- e- Wfrom 35% to 42% of gross income. 2 ?9 j. n! `3 _! B- ~2 p0 Z/ E6 B9 g5 WGDSR(gross debt service ratio)=(payment of principal and interest on mortgage+property taxes+heating costs+50% of condominium fees)/gross income.