Brand new to reptile keeping, need advice

So I'v never been a "snake guy" until I was able to hold a hognose. Now I want one. I'm in school for Zookeeping and I know the basics of keeping herps but as this is my first time actually owning a snake I would like some experienced feedback and advice. I've done a lot of research on them since. Note I don't have one yet, I'm making sure I get everything ready first.

1. I bought a used 75 gallon tank for $20. It came with the mesh lid and was only $20. With it being that big the temp gradient should be good. On the hot side to keep it 90 degrees do I need a high wattage (75-100) heat lamp and a heat pad? On the cool side a lower wattage ceramic lamp? The tank is in my finished basement but tends to get cooler than the rest of the house at night (~60 degrees). I guess what it boils down to, is how can I make sure I heat it correctly and possibly how many lamps would I need?

2. I've read that Aspin is one of the most used substrates. I wouldn't mind using it but was wondering if I could also use the coconut shavings because I like the color better personally. I know hognoses like to burrow and aspin allows that and I'm all for animals being able to do their natural behavior when in captivity, I don't know if the coconut shavings would allow for that. I'm also considering feeding in a separate bucket but that's because that's how we feed our snakes in the facility.

3. Finally, when I'm ready to get my hognose (which would probably be a baby), what do I need to ask the breeder and look at in the snake for healthiness? I'm planning on feeding it mice if that helps.