Long-term? 

I want to help my son get off to a great start but I am also concerned what cosigning will do to my debt to ratio and I have been circling real estate investing for the last few years, ready to take a shot now.

Short term rental or renting it to a family long term?

If the cosigner/guarantor owns real estate for example, any unpaid judgement will become a lien on that property and raise the odds significantly for eventually getting paid.If the cosigner/guarantor doesn't have assets like real estate to go after all they are offering you is a promise and last I checked you can't cash a promise!

For example, RentRedi gave us some trouble in refunding a tenant's security deposit and the customer service representatives also notified me that there is currently not a way to refund a tenant's security deposit after 6 months once the deposit is made which concerned us with long term tenants. 

That said, if you have a really strong tenant with a long term lease, you might find a lender willing to lend based on that. 

Population Growth/Decline (If the population is growing or declining over the last 5 years).5.

The key is to show the long-term benefit, including both the steady income and the future sale profits.If you put together a clear proposal showing the return on investment (cash flow + equity appreciation), it could be a compelling case to bring in a new partner to buy out the current one.

They are the last person you want to tell that you are executing a wrap. 

Also in the Danbury area with short term rentals and a few long term rentals.