[fintstone]

If you are allowed to borrow against a 401K, that has worked well for me in the past as it is essentially a way to briefly diversify and allows you to put it back as you make the loan payments. There is no impact on taxes unless you fail to pay. If you take the money out (done that too), it is treated as regular income (unless a Roth) and drives your taxes way up (assuming you have a relatively high income). That drives up your Medicare costs too (if old enough for Medicare). Plus, you cannot put it back.

Another option is to find a partner/s. and build on more/all of your lots. You would share the return, but you would also share the risk. Often there is an economy of scale.