Who pays what if additional capital is needed for an improvement?

My wife and I were raising 3 daughters at the time and wanted to provide well for my family’s future.

Essentially purchasing and converting a single family home into a home that will house 8-16 seniors and provide caregivers, etc. 

This property was very enticing to my investor as the possibilities of a full 3rd story addition would make this one of the largest homes in the area.

Additionally, is it feasible to manage this without a property manager?

Also, working with a realtor with good social media exposure can be additional free marketing for your property.

Although in Canada it was/is the Ensuite room. and even here on Biggerpockets one lady got on about how she is lobbying in the state of Indiana to have the term Landlord removed from the vernacular and replace with  ( Housing Provider)  the thought being Landlord denotes Lord of the land and superiority over the tenant I guess is the point. 

It is not easy to provide good coaching, I have tried. 

If you have reserves, can you invest the money that provides a better NET return (after tax) than putting it into the down payment3.

I am aware of additional payments for an FHA such as MIP, but i am completely fine with that.