rental income/tax question

[J Basscase]

Hello- I'm new here and am currently making an offer on my first MFH investment property. It's a very old property (late 1800s), so I will be wanting to set aside a good chunk of money in a reserve account for maintenance and Capex.

I'm currently self-employed and write off everything under the sun (that's legal, of course) on Schedule C including all home office & related deductions, most of my automobile miles, cell phone, etc, etc, etc.  At the end of the year, I pay very little in taxes.

By owning a rental property, what ELSE- in addition to everything I already write off- will I be able to deduct?  I'm worried that I won't have enough add'l deductions, and that I'll end up owing quite a bit more in taxes than I currently do.  What am I missing?  I don't really understand this part of RE investing very well, so if anyone could shed some light or share their thoughts, that would be appreciated.  TIA!