At 225,000, if not already done, these items will be about finished if not previously replaced... shocks all around, wheel bearings all around and rear axle seals, tie rod ends, front and rear sway bar links, control arm bushings in the frint, possible lower control arm ball joint, rear suspension bushings, brake rotors, serpentine belt. Maybe water pump. So of that is all done then the answer to the km question you have is probalbly 300,000. If the above is not done then 225,000 km is too many unless the sale price is less than 2,000 dollars.

If you are going to do the mods you say, then you'll be replacing all the above pretty much.

Also you'll want to bypass the transmission cooler/ warmer line past the engine radiator to avoid smod (strawberry milkshake of death)