That's my opinion.Another good one is AppFolio, but this is very costly.

Low Repair Costs: With only $2,500 needed for repairs, the investment required minimal additional funds.

Bridge Loan: Most lenders on BiggerPockets will offer 85-90% of the purchase price plus 100% of the rehab costs.

Unless you are an attorney practicing real estate in the state of the subject property, the chances of reaching a wrong conclusion are too great and the consequences too costly.  

The buyer agreed to a purchase price and all fees/costs.

Many clients from Canada also boast that pricier neighborhoods in the U.S. for example Miami, are only a fraction of the cost of properties in Canada, so their ROI is much higher. 

Is it because the cost of their service is fixed and therefore they try to do as little as possible, or is it something else?

It's in a city (outside the USA in Mexico) that has seen major growth the last 3-5 years and has great prospects to continue growing thanks to nearshoring and high cost of living across the border in the USA.I spoke to an architect and it looks like a 4-unit building can be built on there.

my father has been investing in detroit for 22 years over 100 different properties i am not sure which is the better choice but we always have the tenants fill out an affidavitwater bills in detroit can come in extremely high at times and if the tenant decides to skip out on paying rent and bills, it can cost you thousands if it is under your name and not theirs.

The leverage and arbitrage when used to its full potential far exceed the costs.