I think the answer to your question at least for the cash expenses depends on your particular situation. what portion of the property can the tenant use? can they use the kitchen, living room, dining room obviously the bath. in other words the whole house except for your bedroom, then I think you have a valid argument for deducting 50% of the cash expenses. if they can't then the expenses are mostly attributable to your use and a 50/50 deduction would not be appropriate.
