Last halving on 2016 make the price increase as much $200, however it takes several months to rise until it reaches $900 by the end of the year. During 2016, bitcoin price increase more than 100%, so the best I can expect for this year is $2000 as bitcoin has started this year from $1000. In 2020, I guess bitcoin could reach $4000 but not beyond $5000, if I'm wrong and it turns out more than $5000, I'm happily to say > bitcoin has proven itself exceed my expectations.
If we take this and end of last year as some markers for this to be true for 2020 year in price, then price wont pass for best possible scenario over 6k.
3000-4000 seem like good margin but still its unpredictable to tell what will be price and what to expect from it in any possible way.