Having three full bathrooms will be best for either of these strategies no matter what. 

They do have some options for building up (see three story image below) but we created an apartment that consists of studios units, in the standard 16x74 foot modular home rectangle.

• Suggestions for improvement please.Here is the back story:I recently purchased a three family with inherited tenants occupying two of the three units.

However, 80% of tenants in a recent CBRE survey expect to increase their spatial requirements over the next three years, indicating a shift towards in-person work and future growth.While new demand remains slow, these lease renewals are a positive sign, laying a stable foundation for the office market's recovery.

I'm currently under contract with rent to retirement for three more properties, but after this I may be a little strapped for cash and need to explore more creative options to continue investing with.

Since you have no significant debts and manage your finances well, your existing financial data from tools like Fidelity’s Full View should be sufficient.

As you can see below of our "hard earned capital" invested into three deals. 

Some DSCR lenders will use the new appraised value after three months so you don't have to wait longer than that to get up to 75% loan to value (LTV) cash out. 

You are looking for a combination of 3 things: sufficient vacant land, residential and commercial, all in 1 property and affordable.

If I was evaluating that property, a couple of things would stand out: I agree the 5" slab probably isn't sufficient given the potential for freezing and movement under the slab.