This could cost 10,000 or more depending on your budge, size of unit and quality furnishings.

A Comprehensive Guide to Homebuying, it's essential to be thorough and methodical to ensure you're making an informed decision but draw boundaries, it's okay to open built-in closets and kitchen cabinets to assess the property, However, respect the seller's privacy by not invading their personal space, such as medicine cabinets, storage boxes, or clothing drawers,Interior:Architectural style.Bedroom and bathroom count, size, and location.Closet and storage space.Number of floors.Sightlines and general floorplan.Appliance age and condition.Light switches and socket count.Plumbing and water pressure.Natural light and views.Noise levels.Stairway width and type.Porches and decks.Garage and parking capacity.Proximity to neighboring homes.Remodeling opportunities.Exterior:Roof and siding condition.Landscaping and outdoor maintenance needs.Additional Considerations:Take notes and photos during the tour.Use your five senses to assess the home's condition.Ask your real estate agent questions about the home's features, flaws, and market conditions.Red Flags:Overly scented rooms.Water stains and damage.Lack of maintenance.Foundation issues.Sagging ceiling.Fresh paint that may be covering up issues.Final Tips:Be prepared to make multiple offers before finding the right home at the right price.Stick to your budget when making an offer.Don't overlook potential red flags just because you love a home.

Would this be a sufficient size to add another 1bed/1bath apartment to?

Also decent sized deals for larger fees!

There is no "one size fits all" answer here. 

i guess that depends on the size of the deal.As far as flipping goes,  how is flipping any different from buying a stock and selling it for profit?

I think when you hire a PM you have 3 choices 1)  A very small local provider (<15 units) and they tend to me 1-2 person operations, they are the one unclogging toilets, answering guests, etc and it is tough to do everything, so things lack. 2) A large/nationwide provider where you are only a number and they usually lack local resources 3) A mid size local provider who have resources and you are not just a number.Through effective revenue management with a revenue manager, and being listed on 15+ sites including Marriott Homes & Villas, JetBlue and Allegiant Airlines, Hyatt and Amex Travel (coming soon) we are bringing in more revenue than most can self managing, offsetting our fee.One of the top questions I tell people to ask their manager is the fees, who keeps them? 

Those algorithms compare homes based on general location, size, # of beds/baths, age, etc.

If the price to replace is within budget I'd do it because you're putting out a newer/safer/more reliable product.2) Cost to replace the entire systems is tough to gauge without knowing the building size and style...

There's no one size fits all answer to this question.