I would like to be prepared for a larger multifamily project. 

There are a multitude of roles, stages, and responsibilities for each and every unique project.

Look for areas with solid rental demand, typically in Blue Collar America, where BTR projects are particularly appealing.

How did they perform versus projections?

we did that except instead of renovating it we knocked the existing home down and built a new primary. right after we were completed we had $500k in equity as we acted as the GC on the project. 

The entire project took around 3 months with EVERY square in minus the electrical( some added) being gutted and renewed.

And if they are a hobbyist/part-time builder, then they should engage the proper professionals, i.e. a title officer, civil engineer, architect, contractor et al to assist in reviewing the project's feasibility.

Use the HELOC funds for another investment strategy such as funding fix and flip projects.

Quote from @Clint Miller: Anyone here in the community used construction loans to scale their development projects?

As you’ve already seen, it’s very hard to find cash flowing properties on the West side without a massive down payment.