I recently used one

basically if the net sale price( sold price- cost) is no more than 365k, there is no benefit to use 1031k.  At the end, I had to take the fund out from 1031k and pay the long term gain next year.   Wasting $1250.00..... but learned the lesson. 

you can not use any amount once it is in 1031k for improvement unless you set up another specific account for that--- and if you had downpay for the investment property that was sold,  you can not take it out from the fund---