Investors & landlords

Quick question. I bought a property and did a bunch of improvements to it in 2017 and didn't start rental activities until 2018. For 2018 tax return, can I still add those improvements done in 2017 to my purchase cost to increase my cost basis so that I can take a higher depreciation in 2018 tax return ?

While I am not sure if it matters, the property I bought is a condo with 2 master suites that share living room, dining, and kitchen while each master suite has its own bath inside it. I occupy one suite and a renter occupies the other. Thanks.