I typically draft an extension of the original lease or have them sign a new lease.

 $30,000 in apartment space, due to the nature of the beast, buys potentially a totally different type of product.For instance, $30,000 is surrounded by other $30,000 houses.  

For instance, do they get paid at the end of the investment period in one lump sum plus interest?

For instance, who would hold the money until closing?  

Both times they returned, re-read, and the bill went down drastically to basically the usual amount.In the first instance, I was living in a big apartment complex. 

The COC though is highly dependent on your circumstances. for instance, a buyer that can still do a conventional loan (because they have not done 10 mortgages) can get a higher COC then someone on their 11th property (in most cases). 

I've got extensive experience with rough carpentry, cabinetmaking, flooring, drywall, wiring, plumbing and am confident in my ability to inspect a residential property myself.

Well all 3 were bought for significantly less than their last sale price, and more importantly the previous owners had done extensive remodeling and improvements to the properties, for which I did not have to spend money. 

For instance, if you have an auto loan at a 1% rate, I'd say congrats.

For instance, flipping in a LLC is actually a horrible idea.