Selling vacant land -- seller financing vs installment sale

[Randy Cheval]

I'd like to sell vacant land in Louisiana that I purchased for cash at a tax auction. I have a buyer that wants to buy in installments (They are a neighbor to the land and don't have enough cash for the full purchase price). I've not personally sold or purchased property this way before. 

The property was cheap and there's not much margin -- I bought for $5,600 and am selling for $10,000.

I'm thinking of financing the deal and holding the note at maybe 10%. Or I could do an installment sale where they essentially rent to own. I will use a standard RE purchase agreement for my area.

A few questions:

1) I'd like to use the standard lenders/purchaser agreement for my area (i need to find it), and I know that I'll need to record it, but is there anything else I should be aware of?

2) I'd like to not use an agent and instead use a title company for escrow and making sure all ducks are in a row. Is this reasonable?

3) if I instead sold in installments, is there typically a standard form that I should use to protect me and the seller? would I need to get a custom contract drawn up? Typically, when doing an installment sale, does the seller (me) charge "interest" on the outstanding balance, or would I simply mark up the sales price to some fixed amount (which of course can be calculated using a target interest rate).

thanks.