Being able to do this on a personal level makes sure you are ready for the accounting side of REI.I don't recommend wholesaling because it is not a beginner's level REI skill.  

Do your investors have an expectation of profits based solely on your efforts, skills or experience?

Without knowing the type of house, the age, the scope of work, the level of finishes, the type of contractors, your negotiating skill, the time of year, etc., nobody is going to be able to give you a $/sf average.

The jobs are low-skilled and warehouse type.

You can "market" your skills at the local REI clubs found on meetup website. 

Without knowing the type of house, the age, the scope of work, the level of finishes, the type of contractors, your negotiating skill, the time of year, etc., nobody is going to be able to give you a $/sf average.

Each partner brings different skills, money, experience etc to the deal so there is no standard.

Great problem-solving skills at use...made all that much better because you shared how you did it with others.  

@Diana Muresan thank you... are skilled with this type of funding?

Make sure that you can find matching trim at the store to account for a fair amount of breakage and outside corner shortages.