by swimsuit l mean legskin, bodysuit or jammer. It kinda costs a lot to experiment with them yourself so l could use some advice.

Really, the suit type does not differ by race. Just where a Fastskin or whatever else you race in at a meet.

For Fly & IM events the best choice is a legskin as they give the most freedom of movement in the upper body in the strokes & turns.
You should definitely buy a Speedo. Either & FS-I l or FS-Pro (or LZR if you're rich) depending on how much u r willing to pay.
If u search for a while on the net u should be able to find an FS-I l Legskin for around $140 while FS-Pros r generally around $180. They r both great suits & will not let u down.
The two main sites that l use r http://japanswimshop.com & http://ebay.com
Hope this helps! :)