Further north like Vila de Conde or Povoa de Varzim you can get smoking deals beach side  condos.

@James De Stefano, thank you so much.

They might require the mortgage to be in your name, even if the property is under your LLC.PS: since you're in California ask a real estate attorney or your CPA about the Delaware Statutory Trust and find out if it's a good fit for you.

I do have very close family in the area (St Norbert grads now in De Pere for example) that we visit frequently and this will be one more reason to make the trip. 

There are ways to get around the CA franchise fee for out of state properties by using trusts that are exempt from the fee.I remember that one of them was the use of Delaware Statutory Trust to hold the foreign LLC.

or a series LLC (Delaware)?

You can start smaller properties using local banks am de build from there but you need to know what your doing and learn the business. 

@Mark DavidsonHere are considerations in choosing a Solo 401k provider and bank to provide the account:Solo 401k Bank Account Considerations:Here are some general considerations:If you want access to bank checks, a debit card and/or the ability to ACH funds out, you will need a bank, credit union etc. rather than a brokerage.There are 100s of banks and credit unions that have opened accounts for a Solo 401k.Keep in mind that the bank's role is limited to simply providing the account (i.e. no tax reporting, no recordkeeping, etc.) such you may wish to de-prioritize familiarity with Solo 401k plans and focus on other things that are important to you (i.e. branch locations, fees, etc.).If you want the ability to invest in stocks, mutual funds, etc., you will need a brokerage account.Many brokerage firms will open "free" accounts (i.e. no setup fee, no maintenance fee), which will also come with checkbook access and the ability to wire funds out such that they function as a "hybrid" between a bank and/or brokerage account.If you are looking for names of banks that open bank accounts for Solo 401k plans, there are many banks where we have received positive feedback including Wells Fargo, Bank of America, PNC along with local banks and credit unions just to name a few.

Anyone have experience with this in the Philadelphia/Delaware County, Pennsylvania area?

Quote from @Paul De Luca: Quote from @Michael Modugno: Does anyone have experience in investing in single family homes?