If I invest + finance before financing our home, I fear that it would alter our credit, making it extremely difficult to secure financing for our new build.

Because if enough people hassled lenders about these numbers they'd be more motivated to create enough pushback on the CFPB or HUD or whoever to make alterations. 

Expensive Markets, individual home conditions, and other contextual factors should alter your calculations.  

Not high enough to transition into interest bearing instruments, or alter housing demand.

My primary contractor or project manager if we are only calling licensed guys contractors is my go to on almost all jobs big and small.If it involves altering any of the 4 systems being roof, plumbing, electrical or HVAC we'll bring in a licensed guy so they can pull permits and do it by the book.

Lead times on suppliesAlso, hopefully you and your partner can DIY :)1 PERCEPTIONWhen we make decisions on a remodel, we walk through and determine how simply altering the PERCEPTION of a space can eliminate early buyer complaints - especially about- First Impression (exterior/door/windows/interior entry/colors/flooring)- Space / flow (limited by budget, but not impossible to improve)- Kitchen (cabinets/counters/appliances)- Bathroom ….

Which requires the operator/syndicator to alter their operating agreement documents.

You can replace switches/outlets/lights in their existing location, but any alteration of electrical that involves moving or adding locations requires an inspection.At least I know that is true in AZ and CA, but the codes and inspectors are pretty much in lockstep everywhere nowadays... 

Unless otherwise agreed to, a landlord may enter at any time that is reasonable and 24 hours notice is not requiredIt is interesting that no one has bothered to ask what state as that is very critical information in regards to entryI do not agree with some of the advice above to alter the property by installing a device or adding a lock as that almost assuredly is not allowed. 

@John Woodrich can answer this but I think your plan will need to be altered on this point