Heloc plus hard money for brrrr

[Henry Salinas]

In the Houston area(go Astros) and I’m in the process of getting my first Heloc. Qualified for 100k. My plan is to buy a home right around 100-120k, rehab with 25-30. Then refinance with arv of around 200, in order to finance 130-140. 
The heloc is at 4.5% and hml are normally 12%. So should I use up a good chunk of heloc and minimize the hml cost.  Just looking for input on how others have taken this on.