Aluminum with inboard/outboard

I've been looking for a good sized tin boat that I can use for coldwater trolling big waters here in the Northeast. I found a 1994 Crestliner 1750 Sportfish that has a Volvo Penta 120hp I/O motor that has been certified by a marina (for whatever that is worth). I've never considered an I/O powered boat for fishing before, but this hull would work, it's a decent package with a what appears to be a very nice, solid trailer and the price is right where I need it to be. I know that no matter what any marina says, something that passes an inspection today could fail tomorrow. I'd be welcome to any feedback you guys have before I make this potential mistake later today!! My concerns:

1. It's still very much winter here in NH, so I can't water test this vessel which I do not like. Since I have never owned or serviced an I/O boat, can I get some bullet points to visually inspect when I go to see the boat this afternoon?

2. Trailer has rollers which I always thought were a no no for tin boats but I'm told this was the factory original trailer. Problem or not?

3. It's the small Volvo Penta, 120hp, I'm sure it will be fairly slow for a 2000 lb tin boat. Any ideas what I would expect for top speed?

4. Any idea if I will be able to troll this boat 2 mph without dragging buckets or drift socks? The boat is a good deal for me, but if I have to buy a kicker motor and bracket it will negate any cost savings.

If anyone has any experience with this kind of boat or motor, specifically in regards to fishing coldwater species, I'd love to hear your thoughts.

Picture of the vessel in question:

That 120 HP 4 cyl is not the most refined engine on the market, couple that with the tin boat and I think a fair amount of vibration/noise will be ever present. About the 2 MPH, that depends on how low you can idle that thing, 2 mph IS PRETTY SLOW AND I'd GIVE IT A MAYBE AT BEST. WOT should be anywhere in the 35 MPH area, I have a friend with a 135HP in a fiberglass boat and he gets 42 MPH but it's also a steeped hull design.

I/Os are notorius for wandering when going slow - has something to do with gyro effect I believe. So I would figure in a kicker motor.

Alignment of the outdrive is a big maintenance thing. Ask the seller when it was done last. Usually needs to be done at dealer unless you know your stuff. Bottom line, I/Os are more costly to maintain, IMO. Also heavier & will take more draft.

Well, I brought it home, it may or may not work for trolling but I will give it a shot dragging some 5 gal buckets for the time being. I got it for what I think is a decent price and might even flip it after doing a little sprucing up. If I really like the boat I will get a kicker plate and motor, but that's doubtful. I think an I/O is not ideal for trolling since I can't walk up to the entire stern.