Karen,You might want to check out Custom Homebuilders Solution.

Kitchen has white laminate in okay condition, kitchen and bathrooms have wallpaper in bad condition, one bathroom has slightly rusted light fixtures, the grey wall paint is either gloomy or chic (you choose), backyard has patches from the dog, master bedroom has a weird wood inset, garage has a big dent in the dry wall where someone's car hit it, Where would you invest to make it feel more clean and modern?

I raise capital from institutional investors to provide project financing solutions to developers/builders in the Greater Toronto Area in the form of equity, mortgages, and/or subordinated debt. 

This could be a good solution, but is highly dependent on a lot of things, especially the investor who you would sell the property to.

A rarity in modern times. 

Marc M. you have a few solutions available. 1) flip it and not worry about it.

Is it possible that any 1920s era homes that have been "modernized" don't have an electrical system with a lifespan of nearly 100yrs?

Simply put, I design and implement technical solutions for oil and gas organizations.Currently, I am employed by a major oil and gas company for about 15 years, however, not so certain about the longevity of my career in this field due to incredibly low oil prices.

The solution advocated by many BP posters would have us simply increase our management fee percentage to cover the cost of managing maintenance.

American Family Ins may refer you to their sister company American Modern Ins.