Land purchase-seller financed

[Elaine Fawcett]

I've found some land that I want to purchase for a personal home. I'm closing on a multi family in 2 weeks, my first home purchase in years, and can't support another conventional loan on paper for at least a year. The land seller has agreed to do owner financing for 2 years, giving me time to lock the land up and get my ducks in a row. I'll do a build on the land if the deal goes through. 

I have no idea of what to do to put together a deal. First of all, it's a large property, half of which seems to be wetlands. The other half is buildable. It's in an area of cabins and hunting properties, no electrical or town services. I've called planning dept to ask about what is needed to investigate, and that's as far as I have gone. 

First of all, how do I go about getting someone to appraise the land to figure out what my offer should be? Secondly, how do I structure an offer to adequately protect my interests. I'm looking for advice from anyone who's done these deals before, bonus if you're in CT and can actually provide the service I'm looking for. :)