Best way to book passive losses

[Raman Bindlish]

I am a buy and hold investor and I have been in acquisition phase where I am buying properties and fixing them up and renting them out. In the process, i am accumulating a lot of passive losses every year. Without considering taxes, it get added to equity and I grow my portfolio price but I am not sure if I understand how to benefit from these passive losses in terms of making my investment tax efficient in short term and long term. 

Question: If my net cash-flow from various properties is negative (due to large rehab projects in some of the properties), how best to log them in my tax returns? Is there a way to carry them forward? Or if not, how can I document them to ensure that I can add them to my purchase price when selling to reduce my capital gains taxes?

Some background

- I have a full time day job and nowhere near being classified as Real Estate professional

- All my properties are using conventional financing