I simply would not risk a family vacation on this type of lodging.. plus you don't get any points..

You can certainly simply make payments for your parents as a gift.

If the sunroom is already appropriately permitted and a legal addition then converting the use in the property doesn't require permitting if you are simply repairing the distress. 

If you have old wooden windows, the lead inspector won't bother to take swabs, they'll simply fail you for old wooden (friction) windows.

Once the account is set up and funded through either: a transfer, a rollover or a contribution (or mix of those things) they simply follow the custodian/administrators process for investing.

Second, with this kind of idle cash and a lack of time, I feel like I'd rather do a few big deals, even if they're not as profitable as if I did a bunch of small individual deals - I just don't have the time to dedicate to making $30k.

I never had a C-corp before so I don't know, Can i simply assign interest in the property holding LLC out of my C-corp and to my main holding company. 

You might start by simply looking at the history of the homes you've worked on over the last 5 years.

It simply means you take ownership of a home with the other owners lien, typically a mortgage, in place. 

I lack experience and am limited on local knowledge, for now.