I still tried to reason with her to see if we could repair this, but she hired a personal injury lawyer (who happens to be a cleaning client of her) to start emailing me demanding I give her $125,000 for her 1/2 of the business, or else they are going to file a lawsuit.

Security deposit amountYou can find plenty of examples by searching for "tenant estoppel certificate doc" or exchanging "doc" with "pdf" for more options.Here is an example and explanation: Sample EstoppelSome have a lot of legal jargon but this document does not need to be so detailed.

How are they coming up with a security deposit and a months rent and moving costs for a new apartment?

Depends who you ask and how secure you feel about your income On the one hand being debt free is great, but leverage allows us to build our wealth quicker.RE investors are notorious for being cash poor, so I would avoid thatIf youre able to comfortably save 100k a year and have enough reserves, I think buying leveraged properties is the best way to scale.You could kill two birds with one stone theoreticallyThey say paying an extra month a year towards principal saves you 7 years on a 30 year fixed mortgageUsing that logic you can add 2+ months a year on your primary, and buy 1 property a year and keep enough reserves. 

Quote from @Gary Bonds: Any best practices when attempting to secure business funding from a bank, in the form of a loan or credit?

For this, plan on securing at least 12-15 acres of land.

It also isn't enough proof for a judge in small claims court, if you decided to file on the guest there - you'll need your own rental agreement.

I hope you reported it to the police, if not, you should file a police report and also install cameras because there's an influx of squatter's taking over people's properties recently. 

Built in security as I don't visit the land much as I am in Connecticut.

Assumable VA loans are an excellent opportunity to secure favorable terms, but there are specific rules regarding who can assume these loans.