Your offer, contract, and assignment, documents are the most important documents, as they are the bases for all rights and responsibilities.

What documents do they require, what credit scores do they allow, how do they verify previous rental history, etc.?

These are not typically smooth because even when you meet all their guidelines the lender's investor will usually require more documentation.

I received 2 emails yesterday from Airbnb.

The home buying process typically follows these key steps:Assess Your Finances: Review your credit score, savings, and determine how much you can afford for a down payment and monthly mortgage payments.Get Pre-Approved for a Loan: Work with a lender to get pre-approved, which gives you a clear budget and shows sellers you’re a serious buyer.Find a Real Estate Agent: Partner with an experienced agent who knows the local market and can guide you through the process.Search for Homes: Browse listings and visit properties that fit your criteria (location, size, price, etc.).Make an Offer: When you find a home you like, submit an offer through your agent, including contingencies (financing, inspections, etc.).Home Inspection & Appraisal: Once the offer is accepted, hire an inspector to ensure the home’s condition and the lender will order an appraisal to verify the property’s value.Secure Financing: Finalize your mortgage by submitting required documents and ensuring the lender clears you for closing.Closing: Sign the final paperwork, pay closing costs, and receive the keys to your new home!

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Is there a app or is it through email?

This can get pretty complex, pretty quickly, so just keep that piece in check for audit documentation and make sure you have good records on all of it.

I immediately received an email questioning my decision and why I had only raised the rent on the one unit.

It is a full documentation loan.