Hotels & Accomadation:
We recommend either staying in the city centre, or close to the skatepark. If you are coming for two or more days, then we would recomend staying in the city centre. It's a good location to explore the city, close enough to the skatepark, and easy access from the airport.
For the best value option we suggest Travelodge Manchester Central. It's just a 30 minute walk to the skatepark (or a few minutes by train or taxi) and close to everything you need in the city (and the afterparty).
Other good city centre options are...
Motel One St Peters Square
Innside Manchester
Whiteworth Locke Manchester
Yotel Mancnhester Deansgate
Native Manchester
If you'd rather be close to the skatepark, then we suggest Holiday Inn Manchester West. There isn't many ammenities in that area, but it has parking and is only a 10 mins walk (or 2 min drive) to the skatepark.
Slightly further away, but in a better area is Travelodge Salford Quays. Just a 20 minute walk to the skatepark, and close to the Metro station.
There should be plenty of alternative hotel options available.
If you're coming in a larger group, then getting an airbnb is likely the most cost effective option.