merida is one of my favorite cities on the planet. have been there perhaps 20 times, the first being on my 40th birthday 23 yrs ago. we used to stay at the grand hotel, which is close to the central plaza, and used to be full of antiques. it has gone slightly down hill.. although the last time there was 5 yrs ago, we have stayed more often then at Los Aluxes, which is just another couple blocks but still walking distance from the main plaza. at los aluxes, they have or used to have at our last trip, either a pianist or guitarist at every meal, which to me made difference between eating and dining. i was going to make trip to merida last month, and we found rooms there at 76 usd on i think it was travelocity or one of those sites. the state fair of the yucatan is in november, runs for almost 3 wks and is lovely. called feria x'matkuil, you can google it and site will come up. we usually went for the cattle show which was fabulous and one of best in southern mexico. also many other events at the fair grounds, which are situated on a former henequin plantation.
in vallodolid, there are only about 2 good hotels, or were... they are on the main plaza. if you do travelocity and vallodolid, they will come up. stick to one of those, expect about 40 usd night. they are ok, and vallodolid is charming, it was the capital of that region before merida. http://www.travelocity.com/Valladolid-Hotels-El-Meson-Del-Marques.h2303894.Hotel-Information
ok, here is one we have stayed at in vallodolid - el mason del marques.
on ADO bus, the first class buses are fine and we used them many many times in mexico. if we did not need vehicle as in driving to ranches, we preferred to do bus then taxi /walking in merida. if you are used to city parking etc, also the larger hotels do have parking. when we went in november we usuallly drove, because the fairgrounds are about half hr out of the city. i have heard friends say they can get better deals on wkly cars in cancun than in belize. here they are costly!. but be sure if you rent there that it allows you to drive it over the border. and that the insurance covers you here in belize. i would not want to be taking public transport here in belize and would definitely have a car here.
good choice and good luck.