I went through a similar situation when a railroad crossing arm tore the TPO roof on my 05 Bounder. The railroad payed for a complete new roof ($5,600)plus temporary lodging. I hesitated for the obvious reasons. I had a eternal-bond patch but knew it would effect resale. But the biggest reason to replace was the extended life time of the roof, which was already 7 years old. I knew of a reputable service center to do the work and figured I now had another 15-20 years of life expectancy of the roof and I planned on keeping the rig.
IMHO a new 15-20 year roof is worth something on a used motorhome. Good luck!
Jack H