Tax Question on expensing mileage

[Young Moon]

Hi everyone - I am in the midst of getting my taxes done and my accountant is telling me that because I do not have a separate legal entity to assign my mileage expenses for looking at new properties that I cannot claim those expenses. I have 10 properties that I own (7 in my name and 3 in the name of my IRA LLC). It may be possible to claim the mileage under one of my 7 personally owned properties, but that is not quite right, I think because those miles were accrued in connection with a property I do not own yet. Do i really need to have a separate entity to assign these expenses to?