Open a self directed IRA, solo 401k or both?

[Bill Goodland]

I know this has probably been talked about to death on the forums but I'm just looking for a little bit of advice. So I'm 23 now with a good job and income for my year between college and graduate school. I have been living at home saving/investing almost everything I make into blue chip stocks and vanguard ETFs to hope to start REI once I am out of graduate school in 2019 and making more than double the income I am currently making. My question is whether or not it would be wise to open up a self directed IRA or solo 401k now and put some money aside, or invest in the market on my own(without the tax advantages I know) allowing me more flexibility once I am able to put it towards real estate investments(house hack and hopefully some BRRRR to start). I am trying to weigh the cost benefit of the IRA/solo 401k. And if I open one up now, will that matter if my future job after grad school offers a 401k/403b plan? I understand the desire to not be limited to my access to my funds, but also the benefit of growing wealth tax free/deferred. All input is welcome. Thanks in advance.