I almost at a point where I don't even bother with home inspectors.Some other common issues with older houses, particularly if you will be renting:  lead paint, asbestos, mold (although I find older houses are leaky enough that, as long as the roof drains well, air movement through the building is good and prevents moisture buildup), steep staircases, narrow hallways.But you MUST MUST MUST do a walk-through with an experienced contractor (one who specifically has experience renovating older houses/buildings) prior to placing an offer.  

If you are the buyer, you will want to record you option with the county clerk to put a cloud on the deed to prevent them from selling the property to someone else.

Account ClosedMark is referring to the prohibited transaction rules which would absolutely prevent you from putting an asset you currently own into your IRA or 401k.You can invest a self-directed IRA or 401k into real estate, but as a disqualified person, you would not be able to transact with your retirement account.

I do not know of any laws preventing such an arrangement and I'm pretty sure this is done all the time.  

Encourage the tenant to make certain the litter boxes are changed often to prevent accidents (I keep mine in a bathtub in a bathroom we don't use).  

I am in the process of doing my due diligence to prevent dealing with inexperienced lenders.

What makes that scenario much less likely to happen today are the reluctance of the banks and lenders to leverage themselves that much, the forcing, by regulation, to prevent them from getting too leveraged, and the collapse of those toxic assets that used to be traded around like a game of musical chairs, with the value only set by whoever was dumb enough to pay it, in the hopes there would be a bigger fool down the road. 

I know both you guys try hard to prevent this from happening. 

In other words, I do not think adding a co-signer really prevents a bad tenant from proving to be just that...

My advice for newbies is always to do as much research as you can (and @Casey Miles made a GREAT point about being aggressively patient) but to take the time to ask yourself (and your family) and few important questions to help weed out options and prevent analysis paralysis.