Real estate investing is something you can do actively for the next 50-60 years.

But many Solo 401k clients are starting by setting up a brand new self-directed account from scratch because IRS rules allow large contributions (up to $60,000 per year per participant) into the Solo 401k plan which give them very good start.With small amount of funds you will have very limited investment options.

You don't want to do that wrong as the SEC has very specific rules about who can invest and the paperwork required. 

One rule of thumb that I have learned from hanging around a very experienced lender is that portfolio loans are typically not the right product unless you are getting more than 10 properties.  

Some houses just don't fit into any formal rules we have at the moment.

Is there a particular rule of thumb in how much to drop a price?

I don't know how large your condo complex is, but for condos of 50 or more units, it would be a challenge to get every owner to get to it, and properly clean the vents if it was discovered  vents were never cleaned and it could be a safety hazard.I also had special assessments for new roofs, other building wide improvements at my rental condos. 

Then my mortgage company had a list of things I had to submit, including inspections they performed, before sending back the money.I would think anyone with flood insurance would have to go through the same process of working with the mortgage holder to get access to the insurance funds.Now if the government steps in and offers money to affected homeowners, no telling what rules will or will not be in place around those funds.

As such, the plans will be largely similar in the ability to invest in anything the IRS rules allow for with checkbook control.The only real difference on the investing side is that IRA plans are subject to UDFI taxation on debt-financed real estate investments and 401k plans are not.  

At 50% expense ratio a 5 cap would be 6,480,000. which still would make this a good deal.