1 is if somebody gets a little bit of urine on pants is it enough to just dry clean them in order to daven wearing them?
2 And second does one give maaser after or before taxes?
1 Yes, dry cleaning is sufficient. Urine absorbed in a garment only poses a problem when the garment is wet to the extent it will wet the hand enough to wet what the hand subsequently touches [“tofeach al mnas lhatfiach”].
2 One may deduct taxes from his maaser accounting.
1 Shulchan Aruch O:C 82:2, MIshna Brura s”k 2
2 See Pischei Tshuva, Yoreh Deah 259:1 in the name of the Chavos Yair. See also Shevet Halevi 5:133:4.