There are a few things to consider when you purchase a pump.

Height that the water is going to have to go.
How much flow you want.
Available electric outlets.

I would measure from the bottom where pump is going to be, to the top where the water is going to come out, perhaps add a foot or two just to be safe.

When you look at the box pumps come in, it should say how high the water will go with said pump. A smaller pump that will accommodate your needs will probably have minimal flow. A larger one, more.

My experience with diverters has not been a positive one. I think you should have a separate pump for each thing you want to hook up.

SG

Make sure you have a GFP outlet to plug the pump in.

dcarch