Before you start with a team go to creation zone and create a few keepers.

Make them all for your chosen team, all aged 16-19 and leave the rest.

When you get to attributes, make all attributes (e.g. finishing, volleys etc.) down to 10.

Then, you should have plenty of XP to use on your keeper attributes.

This way, each keeper should be worth £20-35 million (keep one for yourself though)

Note: this only works for keepers as they have only 1 category which applies to them.