diff --git a/R/sim_all.R b/R/sim_all.R
index 7b7a81cb96db7d8914220cd5455e99c09b333cf7..a6f23796460aabba869da6c5c283271a295a083a 100644
--- a/R/sim_all.R
+++ b/R/sim_all.R
@@ -27,6 +27,11 @@ sim_all <- function(nosim=2, resps, destype="ngene", designpath, u){
     stop(" 'resps' must be provided and must be an integer indicating  the number of respondents per run.")
   }
 
+  if (!dir.exists(designpath)) {
+    stop(" The folder where your designs are stored does not exist. \n Check if designpath is correctly specified")
+  }
+
+
 
   designfile<-list.files(designpath,full.names = T)
   designname <- stringr::str_remove_all(list.files(designpath,full.names = F),
diff --git a/R/simulate_choices.R b/R/simulate_choices.R
index 670e08ac2194f040598995ea1f329bd11a474574..b1fbfad0c36a3d8b53e5c8f613367805614cd56d 100644
--- a/R/simulate_choices.R
+++ b/R/simulate_choices.R
@@ -8,7 +8,7 @@
 #' @export
 #'
 #' @examples \dontrun{simulate_choices(datadet, utils,setspp)}
-simulate_choices <- function(data=datadet, utility =utils, setspp, destype) {  #the part in dataset that needs to be repeated in each run
+simulate_choices <- function(data, utility, setspp, destype) {  #the part in dataset that needs to be repeated in each run
 
 
 
@@ -19,6 +19,7 @@ simulate_choices <- function(data=datadet, utility =utils, setspp, destype) {  #
       dplyr::transmute(!!formula.tools::lhs(equation) := !!formula.tools::rhs(equation) )
   }
 
+#  Here one can add additional case-specific data
   cat(" \n does sou_gis exist: ", exists("sou_gis"), "\n")
 
   if (exists("sou_gis") && is.function(sou_gis)) {
diff --git a/man/simulate_choices.Rd b/man/simulate_choices.Rd
index f10c00ad025903f6fec561cc649e8df28a3f08d4..b9cb87d2184e3be878e8eaa36ce1c4541d7e7a98 100644
--- a/man/simulate_choices.Rd
+++ b/man/simulate_choices.Rd
@@ -4,7 +4,7 @@
 \alias{simulate_choices}
 \title{Simulate choices based on a dataframe with a design}
 \usage{
-simulate_choices(data = datadet, utility = utils, setspp, destype)
+simulate_choices(data, utility, setspp, destype)
 }
 \arguments{
 \item{data}{a dataframe that includes a design repeated for the number of observations}
diff --git a/tests/manual-tests/Rbookfull.R b/tests/manual-tests/Rbookfull.R
index e2df748a65333c96a37cbf58bfab23f7b1fd86f7..34bd8ace893bb8e88cfce873ab83cf5452f5fd9a 100644
--- a/tests/manual-tests/Rbookfull.R
+++ b/tests/manual-tests/Rbookfull.R
@@ -3,7 +3,7 @@ rm(list=ls())
 devtools::load_all()
 
 
-
+set.seed(3393)
 
 designpath<- system.file("extdata","Rbook" ,package = "simulateDCE")
 
diff --git a/tests/testthat/test-readdesign.R b/tests/testthat/test-readdesign.R
index 23f49cfc08a21712f072589f518360813361261a..849f213e02cf98cff3340f755f855da0490dd9d4 100644
--- a/tests/testthat/test-readdesign.R
+++ b/tests/testthat/test-readdesign.R
@@ -11,7 +11,7 @@ test_that("file does not exist", {
                "does not exist in current working directory")
 })
 
-test_that("all is correct, but gives a warning", {
+test_that("all is correct", {
   expect_no_error(readdesign(design = design_path, designtype = "ngene"))
 })
 
diff --git a/tests/testthat/test-sim_all.R b/tests/testthat/test-sim_all.R
index c0980ce480acdf6a8c4003da0c192d9efcf5df5e..31d02c2692c9892bd19504eb13c5c092107fc4b0 100644
--- a/tests/testthat/test-sim_all.R
+++ b/tests/testthat/test-sim_all.R
@@ -6,7 +6,7 @@ designpath<- system.file("extdata","Rbook" ,package = "simulateDCE")
 
 notes <- "No Heuristics"
 
-resps =240  # number of respondents
+resps =40  # number of respondents
 nosim=2 # number of simulations to run (about 500 is minimum)
 
 #betacoefficients should not include "-"
@@ -47,3 +47,60 @@ test_that("no value provided for  utility", {
                        designpath = designpath),
                "must be provided and must be a list containing ")
 })
+
+
+test_that("wrong designtype", {
+  expect_error(sim_all(nosim = nosim, resps=resps, destype = "ng",
+                       designpath = designpath, u=ul),"Invalid value for design. Please provide either 'ngene' or 'spdesign'.")
+})
+
+
+test_that("folder does not exist", {
+  expect_error(sim_all(nosim = nosim, resps=resps, destype = destype,
+                       designpath = system.file("da/bullshit", package = "simulateDCE"), u=ul)
+    ,
+               "The folder where your designs are stored does not exist.")
+})
+
+
+
+
+test_that("seed setting makes code reproducible", {
+  set.seed(3333)
+  bsq=0.00
+  bredkite=-0.05
+  bdistance=0.50
+  bcost=-0.05
+  bfarm2=0.25
+  bfarm3=0.50
+  bheight2=0.25
+  bheight3=0.50
+  result1 <- sim_all(nosim = nosim, resps = resps, destype = destype, designpath = designpath, u = ul)
+
+  set.seed(3333)
+  bsq=0.00
+  bredkite=-0.05
+  bdistance=0.50
+  bcost=-0.05
+  bfarm2=0.25
+  bfarm3=0.50
+  bheight2=0.25
+  bheight3=0.50
+  result2 <- sim_all(nosim = nosim, resps = resps, destype = destype, designpath = designpath, u = ul)
+
+  expect_identical(result1[["summaryall"]], result2[["summaryall"]])
+})
+
+
+
+
+test_that("No seed setting makes code results different", {
+
+  result1 <- sim_all(nosim = nosim, resps = resps, destype = destype, designpath = designpath, u = ul)
+
+
+  result2 <- sim_all(nosim = nosim, resps = resps, destype = destype, designpath = designpath, u = ul)
+
+  expect_failure(expect_identical(result1[["summaryall"]], result2[["summaryall"]]))
+})
+