Cost of transporting a body 110 miles-ish.

Magnolia

Keep_pedalling said:

A local cremation followed by having her ashes interred with her husband would be a lot cheaper. She may have wished to be buried but that wish should not put you in debt to catty out.

KP beat me to it but we have done this with my sister and Brother-in-law and will soon be doing it with my husband.  We didn't arrange anything special with the vicar just rocked up with a bucket and spade, picking a time when the church would be quiet.  Peeled back the grass, removed some soil, popped the ashes in the hole, topped up with soil then folded back the grass and tamped it down.

Your mum wouldn't want you and your sister to be out of pocket and she would still be with her husband.

Whatever you choose your mum will be happy either way.  

Personally I would have propped her up in the back seat with a seat belt on.  Safety first sweetie (((hugs)))

polar_pig

When my Mum died last year, we wanted to hold the funeral 200 miles away. The FD was a local firm near the funeral location, but was part of a national alliance of other FD's, such that another local FD near the site of death picked up Mum and took her to the other FD. The cost on the bill for this transport was £700. I'm sure it's not the cheapest option, but that's what we did. 

Flugelhorn

Re ashes in a pre-existing grave - I was a churchwarden and pretty sure that the vicar used to just put the ashes loose in the ground under the turf but when my mother died (in another parish) - it had to be in a box, hole dug in original grave (double time as it was a Saturday) and all covered up again and the stone put back by the diggers. 

Remember OP the costs of all this come from mum's estate so if there is little money there don't go doing anything very expensive - TBH direct cremation locally followed by interring the ashes with Dad will be the most dignified and inexpensive