Sched E, FM Rent, Parent is Tenant, Deprec

Young man purchased a single family home (secured a mortgage for it) closed in March 2022. He rented the property to his Dad at "Fair Market Rent" (according to comps) in Aug 2022 and collected rent each month since then. Between March and July the young man spent $15k in repairs (expenses) and improvements (deprec). The property has a loss for the year.
May he "utilize" the loss on 2022 1040 given the young man spent $15k before his Dad became the tenant in Aug?
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Between March and July the young man spent $15k in repairs (expenses) and improvements (deprec).

Why aren't all of these expenses capitalized as startup expenses?

Between March and July the young man spent $15k in repairs (expenses) and improvements (deprec).

Why aren't all of these expenses capitalized as startup expenses?

Well, the rental isn't his PRIMARY business, isn't his PRIMARY source of income, so the rental is considered passive, and therefore he's not allowed to deduct startup costs. (my understanding)

When was the home listed and available for rent? If the expenses were incurred before it was available (i.e. getting property ready), capitalize them into the building, land, furniture/fixture, or equipment component. If after it was available, look at the capitalization v. expense rules and treat as appropriate.

As long as rents are fair market and the father uses the property as a residence it's just like any other rental.

he's not allowed to deduct startup costs. (my understanding)

He didn't say to deduct them, he said to capitalize them. The two of you are equivocating on the term "startup costs" which may have been a bad choice of words on his part.