Time for a change?

"Mittul viewed my property back in 2014 before I moved overseas for two years; his valuation was in line with another four agencies that I had contacted, although not quite the highest so at the time I decided to opt for another larger firm (X). Things went well for 10 months or so, but as the quarterly checks became less informative, and the annual renewal didn't come with any reduction in fees, I started to question what my 16%(!!) was actually covering. After a long back and forth, I parted ways with X, Mittul came on board and handled the (very inept!) transition, taking away a lot of stress for me. It wasn't until everything was completed that the branch manager of X even contacted me to ask "what can we do to change your mind", but it was too late of course. Coincidentally, my upstairs neighbour had instructed them for the sale of his property, and we had a conversation about our shared experiences; suffice to say they weren't very positive. In the short time Mittul and his team have handled my property, they have gone above and beyond, especially beyond what now seems a nominal amount I pay them by comparison. During a recent tenancy change, I was kept in the loop at every stage, including the management of significant works that needed to be carried out - works that I now realise would have been avoided if X had been more proactive during their checks."