Because not every deal is suitable for every buyer, even if the numbers are perfect.

We've found a few suitable properties but the HOA's vacation rental rules haven't been suitable for us.

Did you find a bank suitable for your needs. 

or is it better to do Lease Purchase for the time being till we have a suitable note buyer?  

Some may or may not be suitable for you depending on how aggressive or conservative you are.

There's a guy who owns a mobile home lot about 2 miles from my house, and some of the land wasn't very suitable for pads, so he built a chain link fence around it and rents out places for people to park RVs, boats, and campers for $80 - $120 / month. 

We come across numerous deals that would be suitable for investors on a daily basis, however, we are struggling to find investors who are ready to purchase.

Firstly, you can create issues surrounding self-dealing violations through the provision of services if you do the work yourself and pay for state fees personally.The LLC itself needs to be specially formed with respect to tax ID and operating agreement to be suitable for use by the IRA and acceptable to the IRA custodian as an investment.Most importantly, firms that specialize in these structures provide guidance with respect to your usage of the IRA owned LLC and proper operation within the IRS guidelines. 

The garage was rented out to a tenant, who I kept on.I increased the rent, and while the garage tenant reluctantly agreed, he complained heavily about all sorts of problems with the garage... rats, leaking, roof gutters, sagging beams etc. etc.As such, I told the tenant that I'm not able to renovate the garage, so if the condition of the garage was not suitable, he could vacate.... and if he wanted to stay, he would have to sign an agreement saying that he was renting the garage knowing it's condition and would be fully responsible to any damage to his property.He's continually ignored/put off replying to my emails. 

They separate the "really bad screens" from the "less bad screens" and make money doing it.And the really bad screens also are housed elsewhere between jail sentences--some call them War Zones or F areas, (and there are people in here that make money housing them in those areas also).So it's probably not a housing issue in the areas we see this happening, as much as it's the local government not wanting a particular segment of their population to move away to (Suitable Housing) in another area--where they will lose Federal Financial Income for themselves and those who "Contribute to their campaigns" (and give them other perks in life to do their bidding).Areas like this typically have homeless populations (who actually need housing), but the local governments seem to do very little to house these people in a decent respectable manner, instead choosing to keep their own pockets (and those of certain of their contributors (and benefactors) lined with Federal Government cash for so-called servicing these people with tax payer provided services and etc...Just my 2 cents...Good Luck!