I like you have a much larger amount of money in a pre tax 401k.However, I think most people downplay the benefits of long term stock market investing and I would suggest one reason to keep the roth money in there.  

If I find a suitable property early, could I negotiate some sort of a "pre-closing" rental/lease to own in order to delay closing until after the relinquished property closing?

That is pretty high considering a commercial loan would be around 5-6% APR.

@Stephanie Potter  I get 1 point and 8% from lendinghome...the rates you quote would be for newbies... not sure if this person is a newbiecrowdfunders are driving down HM rates big time.on the west coast pretty easy to get 10% apr or less which includes rates and points and junk fees.I saw this coming a while back.. and am glad I no longer am doing this lending in any volume pretty hard to compete against these folks.

In that case, you may find CashForMyClosing (singular) to not be a suitable lender unless you can get them to give you the time you will need to do the rehab or unless you can find a HML who will lend you enough pre-rehab to pay off CashForMyClosing (essentially, a pre-rehab refi).Again, transactional lenders offer loan terms measured in days, not months or even weeks.

I am seeing online sites like Quicken or Box Loans advertising around 3.875% (the APR is lower than local rates too).

Without getting into a debate on discrimination, the law references many times a pre-existing inequity in regards to distribution of housing vouchers and burden of housing expenses, stating that certain minority groups are spending 50% of their income on housing which is due to discrimination that makes them unable to secure fair/equal employment. 

I have a suggestion for you, Take a Pre-Licensed Real Estate Course. 

If you look at a PM for a vacation rental in Gulf Shores it's 25%, if you look at it in parts of Myrtle Beach it can be 15%, if you go up to ski properties in Montana it can be 40%.  

Having a loan officer explain that you are already approved to the seller or listing agent, or prove that you are qualified with a pre-qualification letter dramatically helps the process.