Offer your thoughts or opinion on the input financial query or topic using your financial background.

property owned 50/50 between my brother and me
Not sure what you are talking about.  The house isn't part of a business so neither of you can deduct half of normal maintenance and repairs.  It is just the cost of having a house.   The only time this would be untrue is if the thing that you are buying for the house is part of a special deduction or rebate for that tax year.  For instance the US has been running rebates and deductions on certain household items that reduce energy - namely insulation, windows, doors, and heating/cooling systems (much more but those are the normal things). And in actuality if your brother is using the entire house as a living quarters you should be charging him some sort of rent.  The rent could be up to the current monthly market price of the home minus 50%.  If it were my family I would probably charge them what I would pay for a 3% loan on the house minus 50%.   Going back to the repairs... Really if these repairs are upgrades and not things caused by using the house and "breaking" or "wearing" things you should be paying half of this, as anything that contributes to the increased property value should be paid for equally if you both are expecting to take home 50% a piece once you sell it.