Anyway, I could spend more time at work and it would increase my income.

You're going to have a tough time finding a lender, you need to increase your pay or find a new job/partner with someone.

We refinanced our house to increase cash flow, and that will close on July 2nd. 

You would just want to make sure when the lease is renewed that you increase the rent to at least cover their part of the water bill.

You will not increase cash flow by paying down a mortgage.

Once you have a full year with no transactions for the ebay business you can start making the ebay related chart of account categories inactive to hide them which will clean up the chart of accounts.So short answer is I believe it's possible to do everything under your existing LLC, however It increases your liability and is not going to be a very clean transition on your books. 

There are different thoughts on this, but some like to say just managing so they can blame th owner for rent increases, late fees, etc.  

They were impressed with how much research and consideration I put into everything and decided it would be a good idea if we partnered together.

Might need some extra considerations: 1) the market will have to appreciate (Austin is HOT so very possible). 2) will need to find realtor willing / able to discount commission.3) house might need cosmetic updates to align with whatever next summers home design trends are.  

I will take this into consideration.