If you think that is too much, then there are a lot of duplexes in Lakeland which is a good choice if the price is right.

The property under contract I want as my primary is 395 K and in the most excellent location, river front and 3 residential structures are allowed in the land.  

I'm thinking that this would be an excellent place for ground-up self-storage.

On the other hand, if she applies, her credit score is excellent but her income is very little.How does this work?

A call to a town building department, or an internet search should answer that for you.2) I have found The Journal of Light Construction to be an excellent source of information.

Hopefully you were able to verify the new job is legit as well as excellent previous landlord reference. 

My favorite quote from that book is"Anyone who dreams of an uncommon life eventually discovers there is no choice but to seek an uncommon approach to living it"  - Gary KellerTo be successful you can't just copy what someone else is doing exactly, and you don't need to come from wealth and connections in order to be successful in real estate investing.  

As an investor, I had a choice to list any way I desired and I never desired to use the MLS to list my units.  

Pulling a HELOC is also an excellent strategy to obtain cash, in fact many investors use this, however, if you do decide to go down this route you need to run your numbers religiously.

There's no "rules" regarding who has to be on the lease, you can make your own choices but adhering to common practices is probably wise.