Same goes for number of LLCs and what to fund them with, since bear in mind that CA tends to be more cumbersome and expensive to have LLCs than other states. 

LLCs are expensive and paperwork and publicly known.

No...different house....the more expensive one is different quality...all brick, different finishes, different appliances, different lot size, 30 year shingle vs 20 year shingle and so many other details.Dallas vs Collin County....two very very different places......take places like Frisco for example where most homes have been built in the last 20 years vs Dallas where very few homes have been built in the last 20 years. 

Unfortunately, you'll just need to get your pencil out and grab every expense possible in preparing this for sale.

In my market, the multi families are very expensive and the SFH with the MIL basements usually pencil out better. 

Here are some considerations:Higher Initial Investment: Multi-family properties are generally more expensive than single-family homes, requiring a higher down payment and potentially higher financing costs.Management Complexity: Managing multiple tenants, leases, and potential tenant issues can be more complex and time-consuming.Local Market Demand: The demand for multi-family units can vary significantly by location, potentially affecting rental income and property value.If you are more interested in Class A or B properties and have a less cash flow-dependent plan, residential properties can be a simpler place to start.

Some of your renovations can be expenses and some may need to be capitalized.

Is that really net of other "fixed" expenses increasing? 

Increase your income, reduce your expenses, save like a madman, educate yourself, and invest from a position of strength.1.

However if the property is almost paid off I’d look at the cost of the repairs (they’ll only get more expensive if you let conditions deteriorate further) and weigh the costs vs the income you are making.