Looking to buy my second investment property

So over 2 years ago I bought my first investment property. It's an upper/lower duplex that me and my fiancé live in while renting out the upper unit. We are looking at getting another investment property. We don't have much cash on hand to buy and fix up our next property. We've looked into the refi or HELOC paths. We don't want to do a cash out refi due to having a 2.5 interest rate. So we were leaning more towards a HELOC. Is this a smart move? Why or why not? The property we want has been vacant for 2+ years now and it's 4 houses down from us. I Would offer the owner no more than $85,000 and probably needs $30,000-$50,000 worth of work. I Can probably rent it for $1,200-$1,300 when it's all done.