In most cases 50ft of hose with machine at front door or bottom of stairs willl cover your standard home so no need to take upstairs.
WHAT MACHINE that has got to be the most asked question on this forum
second to CLEAN LOL
Your location is a big factor also when buying new say you bought a ninja 135psi good machine but you live in scotland thats a long wat to bring it back even under warranty as you would have to make 2 round trips as its rare they would fix it on the spot
You mention the prochem course you did they would naturaly like to sell you their machine
Ford would sale you a focus before the astra i suppose.
I started cleaning carpets with a prochem steameasy l400 single vac 70psi intank heater
many years ago things have moved on a lot in that time.
The prochem powermax would also serve you well.
Think LOCATION, service ,repairs then machine Any machine with twin 3 stage vac motors with 135psi should be fine with upto 75ft of hose one thing for sure they all go wrong at some point so factor that in your choice.
I am sure other people Would mention different thats the great thing from a open forum.
off to bed now back to school for me in the morning cleaning carpets that is.