There are some considerations when using group aircraft for hour building. The group may not even let you join if they suspect that's what you intend to do. You may find that after you've achieved your goal it's harder to sell your share than you thought and you remain liable for ongoing costs.
Consider someone who is lucky enough with bookings and weather and maintenance to regularly fly 3 hours each Saturday: Once you've driven to and from the airport you can write off that whole day. 33 days to fly 100 hours not considering cost. A better option would be to use holiday allowance from work and go hour building in the US (or better still work those Saturdays and accrue extra leave.) There are plenty of places that will rent you a PA28 by the week and let you fly 8+ hours a day if you want to.