If you partner into large large projects with other investors, do you have the controlling interest?  

@David HinojosaIf you're partnering up with 3 friends I'd HIGHLY advise making sure that you control the major decisions.

Following are the similarities and differences between the solo 401k and the self-directed IRA.The Self-Directed IRA and Solo 401k SimilaritiesBoth were created by congress for individuals to save for retirement;Both may be invested in alternative investments such as real estate, precious metals tax liens, promissory notes, private company shares, and stocks and mutual funds, to name a few;Both allow for Roth contributions;Both are subject to prohibited transaction rules;Both are subject to federal taxes at time of distribution;Both allow for checkbook control for placing alternative investments;Both may be invested in annuities;Both are protected from creditors;Both allow for nondeductible contributions;Both are prohibited from investing in assets listed under I.R.C. 408(m); andNeither may be invested in your ow business. 

Every year without exception, but I am in a rent control environment and have no other option if I want to stay current.

It's lots of work and I was told by the provider "you have more control in this matter." 

(assuming this is a rental, some of the higher-grade commercial finishes would work better in high traffic areas and might keep you from having to screen and recoat as often as you would).  

(Like using the fact that your car insurer will raise your rate $1500 to get out of the court reporting you little $150 traffic ticket -- yes that's from experience!

It will slow down traffic a bit and make the road less blighting.

Using the Control and Roll system - you should never need money to accomplish your financial goals. 

Equity partners will have more control, but charge less than other financing.