I made it clear in an addendum I added to the lease that it was an unfinished basement and any and all improvements that they want to make or do make have to have prior written approval from me or my husband as well as permits and insured licensed contractors for electrical, plumbing, etc.

In order to improve that return on asset you have to either leave the market to go where you can get a better return or you have to leverage. 

The contractor and your inspector are going to be able to help you determine renovation costs, so get quotes and add on 20%.Talk with the RE agent about resale and rental values on the property in current condition and ARV (after renovation value).But the best thing about this scenario is access to the owner!!

If the improvements made were substantial then I might also provide invoices paid to contractors as well as a scope of work to justify financing at a value much higher than my initial purchase.10% vacancy is definitely higher- if you've got a stable property that meets your markets rental demands then I would use your market's going vacancy rate (which may not be representative of your EXACT asset).

This allowing the finances to update and improve the condition of the other 5 homes.

Cozy bought by Co-Starof course they say no change, but hopefully they’ll continue to improve.

Cozy bought by Co-Starof course they say no change, but hopefully they’ll continue to improve.

(D) You could look to generate more cash flow from a small plex unit, where you occupy one unit and rent the others out, and improve over time.  

Is 24hr notice legally needed to access  property's front and back yard? 

I buy from neighboring towns he does not invest in and get the properties low enough it makes sense to take the risk on buying without inside access or utility on.If you assume its paint and polish, you will get burned.