But it seems like there may be a lot of restrictions.

Too much work and responsibility for a small landlord and restrict ability to scale up. 

And, some countries are currently excluded from bank financing due to their currency trading restrictions placed on financial institutions. 

But they usually don't restrict a property so much that you couldn't use one legally as an investment property. 

I tried looking into alternatives like self-directed IRA's to avoid the penalty & taxes but it's extremely restricted, and it seems that the only purpose is to make money for the IRA.

There is no restriction against being employed or having multiple jobs in addition to the business or self-employment activity.

If the parking bumper is standard height and he lowered the car, or it's a factory low car (some are) it seems his insurance should pay.If he hit a parking boulder type rock, then it was his driving that did it.It seems like it might be pretty obvious if you have any part in this depending on what he hit, and if the car is lower than normal.It still seems like he should turn it in to his insurance though.That's how I see it.

Lot size in acres & sqftPrevious use and/or types of structures previously on the lotIs there a Phase 1 environmental  (if applicable)Any deed restrictions and/or HOA covenants Setback requirements (if you can get them from the City) - this is more icing on the cake.

Now we have a ton of extra capital freed up, free to invest with no penalties or restrictions, which generates tax free cash flow that we can use on whatever we want NOW.My parents just turned 60 and are starting to withdraw from their retirement accounts.

You do have a recommendation above and it gets good references here on BP since they do write nationally...but they do have some restrictions.