Do they qualify for a DSCR loan with estimated market rents (use long term average rents, not suped up STR or MTR rental income to be safe).

Since there is already a contract in place saying a real buyer is willing to pay X amount, and an appraisal is an estimate of what the market will determine a property is worth, the contract price is usually what the appraisal comes back at or near in my experience.

I wanted to use the free "rehab estimate sheet" but it prints out with an extremely small font and gray instead of black.

Either they did not do their homework right (appraisal comes in lower than their estimate, insurance/taxes are higher than their estimate, property did not have clear title, and/or the property has deferred maintenance) or they are shopping without having any experience in the industry. 

Most people estimate 5%. 2.

Hey y'all,I've had a lot of previous experience with rentals (single & small multi family, STR) and did my first flip in 2023 (where I lost a very small amount due to contractors taking 3x the estimated timeline), and I'm looking to finally get into serial flipping.

Could anyone give me any estimates of expenses and cash flow based on experience? 

Great post I do believe a lot of people under estimate the COST of holding real estate. 

You can use generic estimates for each of these expenses (which is advisable), but then readjust those estimates for any specific property you are looking at (seriously).

For me when I'm estimating rental income I start by looking at the area for active listings <40 days old with similar characteristics to the home you're looking at purchasing (trying to find same bed/bath count, and same amenities like in CO homes with a fenced yard do very well because everyone has a dog).