I’ve been considering the advantages and disadvantages of buying land/rundown properties and leveling these areas to build cheap kit homes/warehouse homes which can be beautifully designed for cheap and last a long time (quite sturdy as well).These would then be rented out to tenant(s) and potentially have multiple units.

Are there other advantages or disadvantages to getting a commercial mortgage instead of a conventional one?

The disadvantage is you lose your own representation.

Both financing methods you mentioned have great advantages but also come with disadvantages as you've mentioned.

If you had just purchased the note, and obtained the property in satisfaction for said note, either through foreclosure or voluntary conveyance, we'd have a deemed sale on our hands and you'd generally have a taxable event and basis increase, which might be particularly disadvantageous as the market discount bond rules would apply based on your fact pattern.That's not what happened here.  

Main question I have is what are the disadvantages of having common boiler and furnace. 

The new investment SFR I bought has well on property.The water is tested clean.What are the advantages/Disadvantages when renting and the cost of keeping it up over the years?

The surviving joint tenant(s) usually needs only record an affidavit of survivorship and a certified copy of the death certificate to clear the title.However, except for tenancy by the entireties, a major disadvantage is that a joint tenant can sell or give his property interest to a new owner without permission of the other joint tenant(s).If there are only two joint tenants, the joint tenancy is ended by such a conveyance, creating a tenancy in common.That was cut and paste from the web.

There's no advantage of co-ownership and a lot of disadvantages.

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