On the HOA,, it may be like herding independent minded feral cats (think telling a bunch of do it yourself landlords how to keep their lawns)...The fourplex or quad is a hybrid in a way--not full fledged commercial apartments but not single family housing.

I have herd that some States (Or perhaps just Counties) sell Tax Liens over the net.

Mine was buying with (and in) the herd at a 20% below market value property in 2006... nevermind that that was during the peak of the market hype.

Couple this with the current environment: the herd mentality of normal buyers (and a lot of inexperienced investors) is that now is a bad time to buy. 

There are 9 heirs so it is like trying to herd cats for their agent.  

Second, I don’t follow the herd mentality of investing.

Instead of following the herd, take time to figure out what works for you and stick with it.

I'll let others chime in on potential issues of having a boiler system in a rental or flip since I'm not familiar with that aspect, but I will say that if you read up on HVAC forums it seems that radiant heat from boiler systems is preferable from a comfort standpoint.

The public school system is designed to pump out basically trained people who go along with the herd.

Buying for cash also thins out the herd.