Also make sure your tax basis is reduced as part of the sale since your land is being reduced. 

You should look at any limitations on gift taxes though, and she may actually want to structure it around any of this.

These type of people always have a story about the job they're about to get, tax refund coming soon, inheritance, etc. and when you drill down you find out they lack basic things (ID) that would enable them to follow through on their plans.

An accountant would help here, as you can make gifts to family members every year to a certain amount tax-free.Finally, you could simply sign over the dead to your son, if you trust him to pay you back over time.

The seller wants to sell it for $50k but has requested to put it down on paper for $5k, so he can pay less tax; the remaining $45k would just be given under the table. 

Any CPA/EA/Tax Preparer can DO your taxes. 

Purchased for kids future/college fund (maybe relevant maybe not) Mortgage rate is 4.4% currently paying $1149 a month (including taxes/Insurance)Currently rents for $1550 (room for upping rent to $1600+)In the 2 years Ive had it, Ive added a roof(insurance claim),new windows, new bathroom, plumbing.

Even the house is fully paid off, the 1% property tax + 1% maintenance offsets 2% annual gain.

At 25% down I’m looking at roughly $2300 for principal, insurance, and taxes per month on a 30 year loan at 7.6%. 

Landlord friendly, low taxes, and major tech and manufacturing job growth coming down the pipeline.