You can invest it in real estate, stocks etc. my cup of tea is investing in mortgage notes where I know a lot of passive investors use their IRA to invest because it is mailbox money when your buying performing notes and typically they have plenty of equity and provide double digit returns

Working for a developer and having done many deals where we operate and manage and have investors the deal is typically a water fall where.

I wanted to know what the cost is associated with changing the zoning of the property and how long does it typically take?

It may turn out that that it is a typical bill ($80/side).

Once I started taking on rehabs everything changed.My bread and butter was typically buying homes around $100-110k, putting in around $20k +/- on the rehab and driving ARV to around $150-170k. 

From my experience, I have seen that investors typically start off with SFR before jumping into a multi-family project.

The seller pays realtor commissions not the buyer typically.

You can typically only hope for appreciation here. 

I typically use different people for trash out and deep clean.

A project that has a 1 year turn around has a different risk factor than a project on a 5 year or 10 year plan because you must endure a whole cycle which is typically 10 years peak to trough.So if you deal with a  mess which this sounds like then the upside has to be HUGE for your time.