If it's a 4 bed/1 bath home, maybe it's a second bath.
If it's a 1970s home, otherwise in good condition, maybe it's a new kitchen.
If the house itself is fine on the inside but looks like a dump on the outside, maybe some landscaping and fresh paint.
And so on.
The only thing I can add relates to quality:
If the Sellers are going to do a cheap job, just to sell the place, tell them to save their money and just give an allowance in the Contract.
If the Sellers are going to paint in bright colors and use tile for the Kitchen counters, tell them to forget it.