You don't need to use it all but the maximum amount available is a bonus.

Previously a duplex, with one bedroom one bath units, we transformed the property into an SFH with three beds and three baths, the property has a ton of space, which is excellent for the crowded downtown location.

@Kevin Wareham  To add to what @Chris Mason said, you could also look into section 179 and bonus depreciation where you depreciate the entire cost of something in one year, instead of spreading it out over several years. 

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Since 3 bed/2baths are the most desirable among buyers, I have hired a contractor to turn the bonus space on the bottom level of my home to a 3rd bedroom (an option offered by the builder, but I didn't need it at the time).

If they pay, that's bonus money.Learn to screen your tenants better.

That first interior photo shows the amazing transformation. 

The % is  a bonus for you. 

Do you know about all of the new bonus depreciation laws and if you can use an online cost seg site for a small residential property?

Some ideas: provide a sign-up bonus of $500 per property we add.