Doing anything with these attics is usually cost prohibitive.

The IRS rulers prohibit any direct or indirect benefits to you.

Compared to an IRA, Solo 401k contributions limits are roughly ten times higherThere is no custodial requirement for the 401kYou don't need the additional expense and administration of an LLC to have checkbook controlThere is a built in-Roth component whereas IRAs are either traditional or Roth, not bothA spouse can also participate in the same Solo 401k planThe Solo 401k has additional tax benefits over an IRA when investing into real estate using leverageThe penalties for prohibited transactions are less severe, though it's best not to utilize this benefit :)

The PMI on the FHA seemed prohibitively expensive. it was basically a non-starter for us.

and it's fixed for 30yrs               - Some people will mention that the private mortgage insurance is prohibitive to getting the loan, but I just look at it as being part of the total monthly mortgage payment, so it wasn't a deal-breaker for me.Cons:- 3.5% down payment (lol....)

Most are not willing to do this because to do so effectively either cuts into profits, or is cost prohibitive for the owner.

We have been doing this on land deals since the early 80s.. did not invent it.. but we followed the auto industry.and the other reason I did it is I had some Saudi clients that were prohibited from paying interest so I just backed into PV values and they were good with it.We paid our imputed interest.. but you usually get a nice price for the asset.and I can tell U the investors I sold these property to are happy campers as well. the houses did not cash flow and were maybe negative but now 3 to 7 years later they are free and clear and they paid NO interest which is money they cant get back..

Fees for garbage pickup may be included in the owners property taxes; thus, you may be paying for this.In addition, one reason the current landlord may be paying the water/sewer charges on this duplex is that there may be only one meter for both sides (not unusual) and it may be cost prohibitive to run a second meter.   

Not sure if they work in your areas, but I have homes all over Alabama.They have a few rules, like NO trampolines and they prohibit certain types of big dogs.  

I have been trying to start one in DC proper,  however it is finding a meeting space which is prohibitive.