To play both sides and now from the perspective that I need reliable and accurate Scope of Work and Draw schedules for the lenders I think a lot of work needs to be done to get investors and contractors on the same page at least to co exist. I've seen investors come off as contractors are too expensive and want too much upfront and so many are fly by nights whereas contractors believe that some investors are cheap and don't respect their time and investment into their business.
Investors shouldn't use contractors as a courier service. I've seen that firsthand where an investor bought flooring, cabinets and more at off the wall distributors that didn't offer delivery and then expected the contractor to pick up the materials. One such investor had 8 pallets of materials.
Contractors shouldn't expect investors to pay large deposits upfront but should be reasonable like 15-0% with a draw schedule. GC's have to pay for general liability, workers compensation and quite often their subs want small deposits.
Investors who want contractors to do bids or help build a scope of work should probably pay one to do it for them who wont be on the project but can act as a consultant or something. I've thought about creating such a service. Help investors with pricing, estimating, building the scope of work, draw schedule, vetting insurance and licensing.
Just my .02!